Photo Credit: Angie Six via Flickr Creative Commons
As a component of my recent three-part series on NFL rookie quarterbacks, I developed an empirical tool that estimates a “similarity score” for single-season QB performances from 1970 through 2016. This methodology—explained in greater detail here—incorporates five standard measures of passing effectiveness and also controls for differences in a quarterback’s physical tools and playing style. By also including adjustments for year-to-year changes in NFL passing offenses, the resulting tool allows one to make apples-to-apples comparisons between any two quarterbacks’ single-season performances since the NFL-AFL merger.
While my earlier work focused only on the most recent rookie QB class, these next two articles will apply this empirical approach to examine all quarterbacks on NFL depth charts as of May 2017. It is hoped that by publishing a list of every active QB’s best historical player comparisons—based solely on their 2016 performance—that this series will provide perspective on what to expect from each team’s quarterbacks in 2017 and the potential range of outcomes for each player’s career. For Part I of this series, I will focus on the quarterbacks in the AFC.
In order to make historical comparisons, any empirical tool must rely on data that are available and consistent across the entire time period to be studied. Since the goal of my earlier article was to make quarterback comparisons among players in modern NFL history, this approach must rely on the statistics that are available for players from every season between 1970 and 2016. As presented in my earlier study, I have chosen the following five QB rate statistics to measure passing performance:
- Completion percentage (comp / att)
- Yards per completion (yards / comp)
- Touchdown percentage (td / att)
- Interception percentage (int / att)
- Sack percentage [sack / (sack+att)]
Player variations in these statistics should reflect differences in the relative strengths and weaknesses of each player as a passer. However, generating the most effective player comparisons requires more than just passing statistics given that player comps—in any sport—also typically rely on the commonality of playing style and physical characteristics. As a result, this empirical approach also incorporates two other variables:
- Rush yards per game (yards / game)
- Height (inches)
Given fundamental changes in the NFL since 1970, it would be irresponsible to simply compare quarterbacks’ raw statistics across eras. Instead, this empirical approach compares each QB’s seven measures against the NFL average in that season among quarterbacks with 150+ pass attempts. By transforming each QB’s seven values into year-normed z-scores, it is possible to make apples-to-apples comparisons between quarterbacks across eras. In order to generate a singular index of comparability for each QB comparison, I apply a standard Euclidean distance measure (i.e., the square root of the sum of squared differences across all seven z-scores). For an example of how this works, I’d suggest that one review the Cody Kessler/Bernie Kosar comparison here.
So how does one interpret the values of these similarity scores? In reviewing the results for all active quarterbacks, I’d suggest the following guidelines to interpret the numbers:
To summarize, the analysis that follows develops player comparisons based on rate statistics from the 2016 season; career-to-date performance is not (yet) included in the model. Further, I will be limiting the results to only QBs who were of the same age to ensure similar trajectories on the age-performance curve. Finally, I limit the analysis to quarterback seasons with 150 or more pass attempts. This is important given that, within a sufficiently small sample, player performance may be incredibly divergent from their true level of talent. Thus, while I may use this tool to consider active QBs with less than 150 attempts in the player notes below, all historical matches will have met the 150-attempt threshold to be included in the sample.
Again, this article was designed to examine the current quarterback depth chart of every team in the AFC. As a result, quarterbacks are grouped according to their current team and not on the basis of the team for which they played in 2016. For each active QB, his age as of December 31, 2017, is added in parentheses. Finally, each player table features the number of games that a QB has started in the years after the season in question; this is added to provide some perspective on the future performance and longevity of a QB’s best historical comparisons.
Joe Flacco (32)
- Excellent/Exceptional Comps: Kerry Collins.
- Positives: Eight of the 10 QBs were starters for at least three more seasons after age 31… Five of top 10 quarterbacks made it to at least one Pro Bowl after age 31… Six QBs led to their teams to the playoffs at age 32 or older… Kerry Collins (#1) and Carson Palmer (#3) posted Pro Bowl seasons in their late 30s… Craig Morton (#9) led the 1977-79 Broncos to the playoffs—including Super Bowl XII—for three consecutive years in his age 34-36 seasons… Ben Roethlisberger (#10) has been to the Pro Bowl in each of his age 32-34 seasons.
- Concerns: Combined regular-season record of these 10 QBs after age 31 is 207-219-2 (.486 winning percentage)… Combined playoff record of these QBs after age-31 season is 6-11, including 0-1 in the Super Bowl… The play of Collins collapsed at age 32, leading the NFL in interceptions and going 7-21 as a starter with the Raiders in 2004-05… Three QBs in the top five—Troy Aikman (#2), Jim Everett (#4) and Bobby Hebert (#5)—were done as viable NFL starters by age 34.
Ryan Mallett (29)
- Summary: Only had six pass attempts in 2016, so no comparables are available… Started six games in 2015, attempting 244 passes in age-27 season… Top QB comparable at age 27 was journeyman QB Dave Brown (distance=2.50)… Very few close matches for the 6’6” quarterback that season; only four QBs within a distance of 3.0.
Tyrod Taylor (28)
- Excellent/Exceptional Comps: None.
- Positives: Of the 10 closest QB comparisons to Taylor, almost all had long careers; four started at least 100 or more games in their career after age 27… Average QB on the list started 81 games at age 28 or older… Four QBs on the list were named to the Pro Bowl after their age-27 season… Donovan McNabb (#2) was one of two great matches for Taylor; after age 27, McNabb compiled a 55-41-1 regular-season record, a 4-3 playoff record, one Super Bowl appearance (loss) and two Pro Bowls.
- Concerns: While most QBs on this list had long careers, the combined W-L record was just 389-423-2 (.479 winning percentage) after their age-27 seasons… A 12-17 playoff record with just one Super Bowl appearance at age 28 or older… Jeff Blake (#1), the top comparison to Taylor, was largely a replacement-level starting QB after age 27, going 18-30 as a starter with a 58/50 TD/INT ratio from 1998-2005.
Cardale Jones (25)
- Summary: Drafted in fourth round of 2016 NFL Draft… Only 11 pass attempts in 2016.
Nathan Peterman (23)
- Summary: .. Drafted in fifth round of 2017 NFL Draft.
Andy Dalton (30)
- Excellent/Exceptional Comps: Gary Cuozzo, Mark Brunell and Stan Humphries.
- Positives: There are 19 QBs who are deemed as “great” or better matches based on their age-29 season… Most of those 19 enjoyed solid, long-term careers in the NFL at age 30 and older, with an average of 50 games started… Three quarterbacks who won Super Bowls after the age of 29 had a distance score within 2.10: Joe Theismann (#17, distance=1.95), John Elway (#21, 2.02) and Phil Simms (#24, 2.09)… Dalton’s top 10 comparables after his terrific 2015 season as a 28-year old featured some of the best QBs in NFL history, including Donovan McNabb (#1; distance=1.29), Brett Favre (#2, 1.41), Tom Brady (#7, 1.81) and Joe Montana (#8, 1.83).
- Concerns: Returning to Dalton’s age-29 comparisons, a remarkable number of QB in Dalton’s top 10 saw steep declines in performance starting at age 30… The combined regular-season record of the top 10 comparables after age 29 was an abysmal 156-213-1 (.423 winning percentage)… Playoff record of the top 10 at age 30 or older was just 3-7… Only one (Jim Harbaugh) of the top 10 QBs were named to the Pro Bowl after age 29… None of Dalton’s top 16 comparables reached the Super Bowl after age 29… Unexpected top comparison, Gary Cuozzo, was a career backup QB who led the 1970 Vikings to a 10-2 record in his age-29 season before taking his last snap two years later; his career trajectory makes him an ill-fitting comp to Dalton.
A.J. McCarron (27)
- Summary: Did not attempt a pass in 2016… Started three regular-season games in 2015 with a 97.1 QB rating… While 119 pass attempts as a 25-year old in 2015 does not meet minimum 150-attempt to qualify for analysis, the system would have evaluated his best comparison to beP. Losman (distance=1.53)… Given McCarron’s gaudy small-sample statistics, other close age-25 comparisons range from Hall-of-Famers Dan Fouts (1.85) and Troy Aikman (1.87) to other small-sample flashes in Chris Simms (1.89) and Bobby Hoying (1.90).
Cody Kessler (24)
- Excellent/Exceptional Comps: Teddy Bridgewater.
- Positives: The top 10 comparables include seven Pro Bowl QBs, seven playoff starters, three Super Bowl winners and two Hall-of-Fame caliber quarterbacks… After age-23 season, the top 10 QBs compiled a regular-season record of 475-357 (.571 winning percentage)… Combined playoff record of 26-23 with three Super Bowl victories… Even after excluding Brett Favre (#7) and Drew Brees (#10), remaining quarterbacks posted a 174-157 regular-season record (.526 winning percentage) at age 24 and older… Teddy Bridgewater (#1) is Cody Kessler’s best historical comparison—by a wide margin—and was considered the Vikings’ long-term (or at least medium-term) answer at quarterback before his knee injury.
- Concerns: Only five players would qualify as “good” age-23 matches to Kessler… Kessler’s top three comparables compiled just 22 career starts after age 23, although the book is not yet closed on Bridgewater… While Favre and Brees are in the top 10, their distance scores indicate only “fair” matches.
Brock Osweiler (27)
- Excellent/Exceptional Comps: None.
- Positives: After leading the NFL in interceptions at age 26 in 1989, Vinny Testaverde (#1) bounced back to enjoy a 21-year career and compiled over 46,000 passing yards, 11th-most in NFL history… As the other best-case scenario, Joe Flacco (#4) bounced-back from a career-low completion percentage in age-26 season to lead Ravens to Super Bowl victory the following season… Most of the quarterbacks ranked between #11 and #20 had solid, if unspectacular, NFL careers after age 26; this includes Steve DeBerg (#12, distance=2.44), Tony Eason (#13, 2.52) and Kyle Orton (#15, 2.53)… Osweiler’s top comparables for his age-25 season in 2015 with the Broncos were much more favorable, led by Flacco (#1, 1.39); the top 10 featured a varied mix ranging from Chris Simms (#2, 1.56) to Dan Fouts (#4, 1.82) to numerous QBs in between.
- Concerns: Returning to the 2016 list of comparables, eight of the 10 QBs on this list were all but finished as viable NFL starters following similar age-26 seasons… While Testaverde is the top comparison, he was a former No. 1 overall draft pick who may have gotten more chances than Osweiler… There are three “great” comparables to Osweiler; beyond Testaverde, the other two had nondescript NFL careers after age 26… Testaverde compiled a 80-100-1 record as a starter after age 26; the remaining QBs were just 59-68.
Deshone Kizer (21)
- Summary: .. Drafted in the second round of 2017 NFL Draft.
Trevor Siemian (26)
- Excellent/Exceptional Comps: A.J. Feeley and eight others.
- Positives: An enormous number of great comparables, as 31 NFL QBs had a distance score less than 2.0 in their age-25 season… The list of 31 QBs includes Eli Manning (#27, distance=1.95) and Dan Fouts (#31, 1.999)… The 10 closest comparable quarterbacks compiled a regular-season record of 174-170-4 (.506 winning percentage)… Tommy Kramer (#5) and Neil O’Donnell (#9) each went to a Pro Bowl and won playoff games after their age-25 season.
- Concerns: Outside of Kramer and O’Donnell, the rest of the top 10 comparables had largely forgettable NFL careers, although Sam Bradford (#2) still has an opportunity to change the narrative… Three of the top four comparisons failed to start 20 games in the NFL after their age-25 season… Within the top 26 comparables, only O’Donnell (#9) ever led his team to a Super Bowl… The best historical comparable, A.J. Feeley (#1), posted a 66.2 QB rating after his age-25 season compiling a 4-9 record as a starter.
Paxton Lynch (23)
- Summary: Started two games in 2016, attempting 83 passes… Threw just 2 TD and only 1 INT, resulting in both rates serving as outliers… Small sample concerns aside, the system evaluated the most comparable age-22 QB season to be that of Blaine Gabbert (distance=1.93)… No other QB had a distance score within 2.40, reflecting the difficulty in finding matches to an unusual small-sample statistical line.
Chad Kelly (23)
- Summary: .. Drafted in seventh round of 2017 NFL Draft.
Tom Savage (27)
- Summary: Started two games in 2016 season… In 73 pass attempts, Savage did not throw a touchdown pass nor was he intercepted; such unusual small-sample rates result in largely inapplicable comparisons… Only one age-26 QB had a distance score under 3.0, confirming that comparisons are not terribly valid… For what it’s worth, the closest age-26 QB comparison was Jeff George (2.35).
Deshuan Watson (22)
- Summary: Rookie… Drafted in the first round of the 2017 NFL Draft.
Brandon Weeden (34)
- Summary: Did not throw a regular-season pass in 2016… Made four starts with 140 pass attempts in 2015 as a 32-year old; completed 69.3% of his passes with 5 TD and 2 INT… Such small sample success led to top-five comparisons to Neil O’Donnell (distance=1.26), Alex Smith (1.27), Chad Pennington (1.45), Joe Montana (1.72) and Kyle Orton (1.77)… The last time Weeden qualified for this comparison system with 150+ pass attempts was as a 30-year old with the Browns in 2013; top comparisons included Jim Everett (1.78), Dan Pastorini (1.88), Jay Schroeder (1.89) and Marc Bulger (1.95).
Andrew Luck (28)
- Excellent/Exceptional Comps: Ken Anderson and Aaron Rodgers.
- Positives: Nine of the top 10 age-27 comparisons enjoyed long careers as above-average (or better) quarterbacks in the NFL… The top 10 list includes seven QBs who made the Pro Bowl at age 28 or older… Four of those QBs led their teams to the Super Bowl; Terry Bradshaw (#5) and Jim Plunkett (#9) each won it twice after age 27… After their age-27 season, these 10 QBs compiled a regular-season record of 491-392 (.556 winning percentage) and a 29-23 post-season record… The three closest age-27 comparables—those with distance scores less than 2.0—are three of the most accomplished quarterbacks in NFL history… Hall-of-Famers John Elway (#17, distance=2.28) and Tom Brady (#23, 2.35) also feature age-27 distance scores less than 2.40.
- Concerns: Vince Young (#4) may offer some concern, but he posted a 10/3 TD/INT rate as a 27-year old after four lackluster seasons as a starter; his career to that point was vastly dissimilar to that of Andrew Luck… Any other problems with Luck’s age-27 comparables would be nit-picking… Luck had a unique and highly disappointing age-26 season in 2015; no QB had an age-26 distance score less than 2.35… For that season, his top 10 comparables for that campaign were largely NFL journeymen or worse, led by Billy Joe Hobert (#1).
Scott Tolzein (30)
- Summary: Has only three professional starts in his career… Started one game and attempted only 37 passes in 2016… Applying small-sample statistical line to his 2016 season, only five QBs posted age-29 distance scores less than 3.0; all had largely nondescript NFL careers.
Blake Bortles (25)
- Excellent/Exceptional Comps: Archie Manning, Terry Bradshaw and Trent Dilfer.
- Positives: Top 10 QB list includes three Super Bowl winners and two Hall-of-Famers… Top four QB comparables were Pro Bowlers after age 24… Top seven comparables averaged 105 games started in the NFL after their age-24 season… Top 10 QBs compiled a 397-359-1 regular-season (.525 winning percentage) record in their age-25 season and beyond… Fourteen QBs feature an age-24 distance score less than 2.0, including Andrew Luck (1.95); Troy Aikman (2.04) sits just outside of this range.
- Concerns: A common critique of Bortles is that he compiled most of his 2016 numbers in garbage time; the model does not account for this… While top comparable Archie Manning had a long career in the NFL, he posted a ghastly 25-77 record as a starter after his age-24 season… For QBs ranked #11-25 on this list, many of them washed out with less than 25 games started in the NFL after their age-24 season including former first-round draft picks Kyle Boller (#11, distance=1.88) and Jack Thompson (#12, 1.91).
Chad Henne (32)
- Summary: Has not thrown a regular-season pass in either 2015 or 2016… Last reached the 150-attempt threshold in 2013 when he started 13 games as a 28-year old for the Jaguars… Best historical comparable for age-28 season was Steve Spurrier, with an astonishingly close distance score (0.72)… Other top five comparables include Mike Phipps (1.02), Steve DeBerg (1.18), Lynn Dickey (1.25) and Jerry Rhome (1.26)… Twenty QBs posted an age-28 distance score less than 2.0, including Jim Kelly (1.79) and John Elway (1.89).
Brandon Allen (25)
- Summary: Did not throw a regular-season pass in 2016… Drafted in the sixth round of the 2016 NFL Draft.
Alex Smith (33)
- Excellent/Exceptional Comps: Kyle Orton, Archie Manning and Charley Johnson.
- Positives: Twenty QBs posted an age-32 distance score less than 2.0, including Joe Montana (#19, distance=1.97)… Of those 20 QBs, eight started at least 39 more games in the NFL in their age-33 season and beyond… Among the top 10 quarterbacks, Rich Gannon (#4) and Brad Johnson (#9) each led their teams to the Super Bowls at age 33 or older; Johnson was a “game manager” who guided the Buccaneers to the title in Super Bowl XXXVII… Steve McNair (#6) led the Titans to a 13-3 record at age 33… Steve Beuerlein (#10) made the Pro Bowl and led the NFL in passing yards at age 34… Top 10 QB comparables posted a regular-season record of 150-147-3 (.505 winning percentage) and a 7-5 postseason record.
- Concerns: Smith’s best two historical comparables never won another game as a starting QB after their age-32 season; Kyle Orton (#1) never played again and Archie Manning (#2) went 0-10 from 1982 to 1984… Of the top 12 comparables, seven were largely done as effective NFL starting quarterbacks after their age-32 season… For QBs ranked between #11 and #15, none started more than 18 games at age 33 and older.
Patrick Mahomes (22)
- Summary: Rookie… Drafted in the first round of the 2017 NFL Draft.
Tyler Bray (26)
- Summary: Undrafted player entering his fifth professional season… Has yet to take a snap in an NFL regular-season game.
Philip Rivers (36)
- Excellent/Exceptional Comps: Jim Plunkett.
- Positives: Top-ranked comparison, Jim Plunkett, led the Raiders to a victory in Super Bowl XVIII at age 36… John Elway (#7) led the Broncos to Super Bowl victories in his age-37 and age-38 seasons… Dan Marino (#8) led the Dolphins to three consecutive trips to the playoffs in his final three seasons from 1997 to 1999… Top 10 QBs compiled a terrific 115-75 record in the regular season (.605 winning percentage) and a 12-6 mark in the postseason.
- Concerns: Of the four QBs with a distance score less than 2.0, only Plunkett remained an NFL starting quarterback after age 36 and he didn’t start more than eight games in any of his last three seasons… Boomer Esiason (#5) also retired after his age-36 season… None of the 16 QBs with distance scores under 3.0 started more than 44 games in the NFL following their age-35 season.
Kellen Clemens (34)
- Summary: Attempted only one regular-season pass in 2016… Has not started an NFL game since 2013 in his age-30 season… Top QB comparable after his 2013 season was Marc Bulger (distance=1.10)… Others in the top five of the age-30 comparison are Tommy Kramer (1.26), Wade Wilson (1.32), Chris Miller (1.35) and Dan Pastorini (1.40)… Of the top five, only Wilson started more than four games in the NFL in their age-34 season or afterwards.
Ryan Tannehill (29)
- Excellent/Exceptional Comps: Shaun Hill and three others.
- Positives: Twenty QBs posted a distance score less than 2.0, including Jim Kelly (#5), Matt Hasselbeck (#10), Ken Stabler (#15) and John Elway (#20)… Troy Aikman (#21, 2.01), Eli Manning (#22, 2.06) and Tom Brady (#23, 2.06) sit just outside the 2.0 threshold… Among top 20 QB comparables, six started at least 91 games in after their age-28 seasons… Within the top 10 QB list, the players combined for a 286-260 record (.520 winning percentage) at age 29 and older… Five QBs within the top 10 was named to the Pro Bowl at some point in their career after their age-28 season… Kelly and Hasselbeck led their teams to the Super Bowl later in their careers.
- Concerns: Of the top four comparables, none led their team to the playoffs while age 29 or older… Beyond the top 10, the next four comparables had largely nondescript NFL careers after their age-28 season…. Shaun Hill (#1) has been a lightly-used backup since his age-30 season… Marc Bulger (#2) made the Pro Bowl in his age-29 season before his career collapsed, compiling a 70.9 QB rating and a 5-30 record in his final three seasons in the NFL.
Matt Moore (33)
- Summary: Started three games in 2016, his first NFL starts since 2011… In 87 pass attempts, Moore tossed an astounding 8 touchdowns with three interceptions, good for a QB rating of 105.6… Did not meet the 150-attempt threshold, and unsustainable small-sample touchdown rate largely invalidates list of comparables… For what it’s worth, only one QB—Brett Favre (2.85)—had a distance score less than 3.32.
Tom Brady (40)
- Excellent/Exceptional Comps: None.
- Positives: Warren Moon (#1) and Brett Favre (#5) have demonstrated that it is possible to be an effective starter in the NFL in one’s 40s… Moon was named to the 1997 Pro Bowl at age 41 after leading the NFL in passing yards per game… Moon was a starting QB through his age-42 season… Favre was named to the 2009 Pro Bowl at age 40, leading the Vikings to the NFC Championship Game.
- Concerns: Including Brady, there are only nine players in modern NFL history with 150+ pass attempts in their age-39 season… There are only two QBs with distance scores less than 3.0, as the others have distance scores that render them ineffective comparisons… Since one of those two QBs—Jim Plunkett (#2)—retired after his age-39 season, Moon represents the only viable comparison for Brady entering the 2017 season… Moon’s performance was strong in 1995 and 1997, but dipped badly in his age-40 season in 1996 (7/9 TD/INT ratio).
Jimmy Garoppolo (26)
- Summary: After being drafted in the second round in 2014, Garappolo made his first two regular-season starts in 2016… Threw four touchdowns and zero interceptions in 63 pass attempts, completing 68.3% of his throws… The 0.0% interception rate in such a small sample largely renders statistical comparisons invalid… For what it’s worth, the only two quarterbacks with distance scores less than 2.0 are Brian Griese (1.20) and Drew Brees (1.48)… The elite small-sample numbers lead the rest of the top 10 to predictably feature multiple Hall-of-Famers but, again, this is misleading due to the small-sample size and unsustainable interception rate.
Jacoby Brissett (24)
- Summary: A third-round pick in the 2016 NFL Draft, Brissett started two games in his rookie season at age 23… With no touchdowns and no interceptions in 55 pass attempts, statistical comparisons are largely useless… For what it’s worth, the only age-23 QB comparison with a distance score less than 3.0 was Neil Lomax (2.48).
Josh McCown (38)
- Excellent/Exceptional Comps: None.
- Positives: Carson Palmer (#2) is still viewed as a viable starting QB in the NFL… Dave Krieg (#3) led the NFL for quarterback’s lowest sack percentage in going 6-6 as a starter for the 1996 Bears… Earl Morrall (#4) went 11-0 as a starter for the 1972 Dolphins in his age-38 season… Warren Moon (#6) made the Pro Bowl three times between the ages of 38 and 44.
- Concerns: Only four QBs feature an age-37 distance score within 3.0 of McCown… The only reasonably close match to McCown—Gus Frerotte (#1)—retired after his age-37 season… None of the top four quarterbacks started more than 12 games the rest of their careers after their age-37 season, although Palmer may change that in 2017.
Bryce Petty (26)
- Summary: A fourth-round pick in the 2015 NFL Draft, Petty started four games for the Jets in 2016… With 133 pass attempts, Petty just missed the threshold to be included in the sample… Season statistics are not extreme in any one category, suggesting that small-sample comparisons may have some validity… Two QBs scored as solid fits with Petty, led by Matt Robinson (distance=1.00) and Jim Plunkett (1.89)… While Plunkett developed into a Super Bowl-winning quarterback, Robinson did not start another game in the NFL after his age-25 season with the 1980 Broncos… Twenty QBs posted a distance score between 2.0 and 3.0 in their age-25 season… Jake Plummer (2.09) and Jeff George (2.26) were the third- and fourth-best comparables… While the list of 20 QBs between 2.0 and 3.0 also feature Kerry Collins, Rich Gannon and Vinny Testaverde, an astounding nine of the 20 did not start another game in the NFL after their age-25 season; three others started four games or less.
Christian Hackenberg (22)
- Summary: Did not take a regular-season snap in 2016… Drafted in the second round of the 2016 NFL Draft.
Derek Carr (26)
- Excellent/Exceptional Comps: Steve Walsh.
- Positives: The list of Carr’s top 10 comparable QBs includes eight playoff starters, six Pro Bowlers, 2 league MVPs and a future Hall-of-Famer… Top 10 QBs compiled a regular-season record of 412-330-1 (.555 winning percentage) after their age-25 season… List of QBs also compiled a 19-17 playoff record at age 26 and older… Matt Ryan (#3) has been one of the best quarterbacks in the NFL since his age-25 season, culminating in the NFL MVP award in 2016… Drew Brees (#9) also took an enormous leap in his age-25 season and has consistently been among the best QBs in the game every season since… An amazing set of QBs lurk just outside the top-10: Eli Manning (#11, distance=2.09), Matthew Stafford (#12, 2.10), Brett Favre (#13, 2.12), Tom Brady (#14, 2.15) and Joe Montana (#16, 2.19).
- Concerns: Steve Walsh (#1) was an unexpected top comparison… Walsh led the NFL in sack percentage at age 25 and posted an 11/6 TD/INT ratio, but his career prior to that point has little resemblance to Carr’s… Koy Detmer (#6) saw his first NFL action in his age-25 season and barely reached the 150-attempt threshold to be included in the sample; his career trajectory also differed from Carr… Chris Miller (#2) may represent a better career match, as the former first-round pick made the Pro Bowl at age 26 and was posting a career-best season at age 27 before a series of concussions derailed his career.
Connor Cook (24)
- Summary: Drafted in the fourth round of the 2016 NFL Draft… Regular-season duty limited to just 21 attempts in Week 17; not enough for meaningful comps… Started Oakland’s playoff loss, however post-season statistics are not included in the model.
E.J. Manuel (27)
- Summary: Former first-round pick started one game for the Bills in 2016, attempting only 26 passes… Last tossed 100+ attempts in his age-24 season in 2014… His 2014 season featured one “exceptional” match in former Buffalo QB Trent Edwards (distance=0.69); second was John Friesz (1.18)… Last reached 150-attempt threshold in his rookie season in 2013 when he started 10 games for the Bills… Top age-23 comparison was Archie Manning (0.99).
Ben Roethlisberger (35)
- Excellent/Exceptional Comps: Eli Manning, Dan Marino and Steve Grogan.
- Positives: Top 10 QB comparables list includes some of the greatest QBs of all-time… Every player in the top 10 played at least two more seasons; only Dan Fouts (#5) retired after his age-36 season… Four players on this list made the Pro Bowl at age 35 or older… Excluding Tom Brady’s (#8) regular-season 59-17 record since his age-34 season, the remaining nine QBs compiled a 141-128-4 record (.524 winning percentage)… While still too early to evaluate the post-34 career of Eli Manning (#1), Dan Marino (#2) led the Dolphins to three consecutive playoff appearances from age 36 to 38… Brady has led the Patriots to five consecutive playoff appearances after his age-34 season, including two Super Bowl titles.
- Concerns: Four of the top 10 are active QBs, making historical perspectives a bit cloudier… Only three of the top six comparables led their team to the playoffs after their age-34 season… Of the top 10, no one besides Brady was able to lead his team as far as the conference championship game… Steve Grogan (#3) barely reached the 150-attempt threshold in his age-34 season and was a part-time starter for the last 10 years of his career; a vastly different career profile than Roethlisberger all but invalidates the comparison.
Landry Jones (28)
- Summary: Has only started four games in his four-year NFL career… Started two games in 2017, attempting 86 passes and posting decent small-sample numbers (4 TD, 2 INT, 61.6 completion percentage) in his age-27 season… Small-sample caveats aside, top five age-27 comparisons include Eli Manning (distance=1.08), Jack Trudeau (1.11), Jack Thompson (1.28), Joey Harrington (1.35) and Tony Banks (1.45).
Joshua Dobbs (22)
- Summary: Rookie… Drafted in the fourth round of the 2017 NFL Draft.
Marcus Mariota (24)
- Excellent/Exceptional Comps: None.
- Positives: Top 10 QB list includes four quarterbacks that have been viewed as “elite” or appear on their way to that status: Matt Ryan (#3), Andrew Luck (#4), Dan Fouts (#8) and Matthew Stafford (#9); Dak Prescott (#5) may also make that leap… Ryan and Luck both have distance scores of 2.20 or less, implying good matches to Mariota… While Prescott is a year behind Mariota, seven of the other nine QBs were starting quarterbacks on playoff teams, including two Super Bowls… Five of those nine also reached the Pro Bowl after their age-23 season… At age 24 and older, list of QBs has compiled a 296-285 regular-season record (.509 winning percentage).
- Concerns: Many in the top 10 are still young QBs in the NFL, clouding the historical perspective… Only two “great” historical comparables… After leading the NFL in passing touchdowns at age 23, Daunte Culpepper’s (#1) career as a top-notch starting QB ended abruptly in his age-28 season; he held on as a backup through age 32… While the comparables listed earlier for Blake Bortles (#2) are generally favorable, it would be difficult to call him a “success” yet… Shaun King (#6), David Woodley (#7) and Byron Leftwich (#10) only had brief runs as starting quarterbacks in the NFL.
Matt Cassel (35)
- Summary: Started one game in 2016, tossing 51 attempts… Last crossed the 150-attempt threshold in 2015, starting eight games for the Cowboys and Bills as a 33-year old… Top five age-33 comparisons for his 2015 season include Matt Hasselbeck (distance=1.76), Sean Salisbury (1.84), Marc Wilson (1.92), Brian Griese (1.93) and Jay Schroeder (2.01).