What follows is our final Quarterback Report of the 2013 regular season, one aided enormously by research from Jacob Nitzberg of ESPN Stats & Information. The goal of this post has been to provide some level of insight into quarterback play that isn't readily available via traditional statistics and analysis. I'm sure we've been more successful in some cases than others, but I hope the information has been valuable.
Quarterbacks are listed in order of their Total Quarterback Rating (QBR) for the season, but this isn't intended to be a ranking of performance. QBR takes into account much more than passer rating, including things such as game situations and scoring margin that affect some quarterbacks more than others.
Final QBR: 85.1
Final passer rating: 109.0
Analysis: Albeit with a small sample size, McCown had the NFL's best QBR overall, on third down and against the blitz. He completed 46.4 percent of his third-down passes and 51.2 percent of passes that traveled at least 15 yards downfield. Both percentages ranked third in the league. His touchdown/interception ratio of 13-1 was the second-best in NFL history.
Final QBR: 82.9
Final passer rating: 115.1
Analysis: We all know Manning set the NFL record for most single-season passing yards and touchdowns. He also had the league's best completion percentage in the red zone (71.8), and his sack rate of 2.7 percent of dropbacks was the league's lowest. His 10 interceptions in 659 attempts translated into a career-low interception percentage of 1.5. And, speaking to his aggressive nature this season, 27 of his touchdown passes came on first down. The league's next-best performer had 15.
Final QBR: 71.7
Final passer rating: 105.5
Analysis: Why did Rivers lead the NFL in completion percentage at 69.5? Among other reasons, he and the San Diego Chargers worked the short game better than nearly any team. His average air yards per attempt -- the distance the ball traveled past the line of scrimmage -- was 7.68, which ranked No. 30 in the league. When throwing on third down, Rivers converted a higher percentage into first downs (49.4) than any other quarterback. He also handled pressure well, ranking No. 3 in the NFL in completion percentage when under duress (50.0).
Final QBR: 70.5
Final passer rating: 104.7
Analysis: In becoming the first quarterback to produce consecutive 5,000-yard seasons, Brees proved to be the most effective downfield thrower this season. An NFL-leading 17 of his 39 touchdown passes traveled at least 15 yards downfield. He also had his lowest interception percentage since 2004 (12 in 650 passes, 1.8 percent), but was sacked a career-high 37 times -- 10 more than his previous high mark.
Final QBR: 69.0
Final passer rating: 119.2
Analysis: As you're probably aware, Foles achieved the third-highest passer rating and the best touchdown-interception ratio (27-2) in NFL history. He also played dramatically better on the road (83.7 QBR, No. 2 in NFL) than at home (43.9, No. 29). Throwing 27 touchdowns in 317 attempts gave him the league's best touchdown percentage (8.5). He was especially effective throwing outside the pocket and downfield, hitting on eight touchdowns in that manner -- three more than the next-best performer. He also averaged 14.24 yards per completion, more than a full yard better than anyone else.
Final QBR: 68.7
Final passer rating: 104.9
Analysis: Rodgers essentially played only half the season but produced some interesting trends nonetheless. He averaged fewer air yards per attempt (7.65) than any of his other seasons as a starter, but this season the Packers' receivers produced an average of 6.5 yards after the catch for him -- the highest total of Rodgers' career. That all translated into an average of 13.1 yards per completion, the NFL's third-best mark. His receivers also dropped 3.8 percent of his passes, the lowest figure in Rodgers' career as a starter.
Final QBR: 68.6
Final passer rating: 91.6
Analysis: Kaepernick didn't experience nearly as much success in the read-option and other designed running plays this season, averaging 2.6 yards per play in those instances compared with 5.4 YPP in 2012. He was productive as a downfield passer, averaging 9.5 air yards per attempt and 13.16 yards per completion. Both ranked second in the NFL. His QBR of 82.0 on the road ranked No. 3 in the NFL and will be a relevant factor in the San Francisco 49ers' push to Super Bowl XLVIII.
Final QBR: 66.4
Final passer rating: 89.2
Analysis: Cutler's association with new Chicago Bears coach Marc Trestman produced the best completion percentage (63.1) and touchdown percentage (5.4) of his Bears career. Those figures came even as Cutler had the fourth-highest average air yards (9.16) per attempt. He also led the NFL in fourth-quarter QBR at 92.5.
Final QBR: 62.0
Final passer rating: 87.0
Analysis: Luck improved off his impressive rookie season, but the loss of receiver Reggie Wayne clearly hurt him and the Indianapolis Colts. He cut his interceptions in half (from 19 to nine), improved his completion percentage from 54.1 to 60.2 and took nine fewer sacks. He also scored three rushing touchdowns on scrambles (as opposed to designed runs), tying him for first in the NFL. His QBR, however, was 51.1 after Wayne's knee injury as opposed to 71.9 before it.
Final QBR: 61.1
Final passer rating: 89.6
Analysis: Injuries to his top two receivers, Julio Jones and Roddy White, forced Ryan to look short more often. His average air yards per attempt was 6.61. (For context, his career average was 8.4 air yards/attempt before this season.) He was sacked 44 times, 16 more than in any previous season, and threw a career-high 17 interceptions (albeit in a career-high 651 attempts).
Final QBR: 61.1
Final passer rating: 87.3
Analysis: Based on QBR, at least, 2013 was Brady's worst season since at least 2006, when tracking began. He took more sacks (40) than he had in his previous 11 seasons, registered the second-worst completion percentage (60.5) of his career and had his lowest total of touchdown passes (25) in a full season since 2006. On the other hand, the New England Patriots are the AFC's No. 2 seed in part because Brady led them to a career-high five fourth-quarter comebacks. His QBR in the fourth quarter this season (78.8) ranked fifth in the NFL.
Final QBR: 59.5
Final passer rating: 96.7
Analysis: Romo's season will be remembered by many for fourth-quarter interceptions he threw against the Denver Broncos and Green Bay Packers, but it's also worth noting that he threw more fourth-quarter touchdowns (10) than any quarterback except Peyton Manning (14). Romo also tied his career low with a 3.1 touchdown/interception ratio. The Cowboys' offense didn't get downfield nearly as much as it usually does, and Romo recorded career lows with 7.16 yards per attempt and 11.19 yards per completion.
Final QBR: 58.9
Final passer rating: 101.2
Analysis: Wilson was blitzed more often this season (41.6 percent of dropbacks) than any other quarterback, possibly because of the Seattle Seahawks' injury-plagued offensive line. But he led the NFL in passing yards in those situations, and his QBR against the blitz (77.0) was the fifth-best in the league. He also led the league with 51 scrambles, 434 yards and 23 first downs.
Final QBR: 56.2
Final passer rating: 88.8
Analysis: A clear pullback in the frequency and difficulty of Newton's throws helped spearhead a division title. He finished the season with the fewest attempts (473) and yards (3,379) in his career, but he also set career highs in completion percentage (61.7) and touchdown passes (24). Newton remained highly effective as a runner, leading all quarterbacks with 585 yards and tying for the league lead with six rushing touchdowns. He converted 45 first downs on the run, 14 more than any other quarterback. Of that total, 31 came on third down. The next-highest performer was Luck with 14.
Final QBR: 55.8
Final passer rating: 88.8
Analysis: Dalton had a career year in terms of passing yards (4,296) and touchdowns (33) but also threw 20 interceptions and lost three fumbles. Opponents blitzed Dalton on 33.5 percent of his dropbacks, a lower rate than for 13 other quarterbacks, but he led the NFL with 17 touchdown passes (more than half of his season total) against it. He also threw seven of his interceptions against the blitz, tied for the second most in the NFL in those situations. He targeted receiver A.J. Green 178 times, 100 more than his next most frequent target.
Final QBR: 55.4
Final passer rating: 82.0
Analysis: Fitzpatrick started nine games in place of injured Jake Locker and was oddly successful as a fourth-down thrower. He completed six of seven attempts in those situations, converting a first down on all six -- the highest conversion rate among quarterbacks with at least two such attempts.
Final QBR: 54.3
Final passer rating: 92.0
Analysis: The Pittsburgh Steelers' offensive woes left Roethlisberger to attempt a career-high 584 passes, getting him a career high in completions (375). Not surprisingly, he led the NFL with a completion percentage of 72.9 percent when throwing outside the pocket. (Ryan had the next-best figure at 61.3.) His six fumbles lost tied for the most among quarterbacks.
Final QBR: 52.5
Final passer rating: 84.2
Analysis: Stafford's late-game issues in the second half of the season have been well-documented. (He had a 12.3 QBR in the fourth quarter/overtime after Week 9). It's worth noting he had an NFL-high 7.3 percent of his passes dropped over the full season. On the other hand, he was protected relatively well. He was sacked on a career-low 3.5 percent of his dropbacks. The only quarterback with a lower percentage this season was Peyton Manning.
Final QBR: 51.9
Final passer rating: 83.9
Analysis: Palmer fired downfield at will this season in Bruce Arians' offense, ranking third among all quarterbacks in completions on passes that traveled 15 or more yards in the air (65) but also throwing the most interceptions (13) on such throws. His overall totals of 4,274 yards, 22 interceptions and 41 sacks were career highs.
Final QBR: 51.2
Final passer rating: 77.9
Analysis: Ponder's tendency toward hesitant and conservative decisions played out in his final numbers. He ranked last in the NFL in yards per completion (9.08) and was sacked 27 times in nine games, giving him the league's highest rate of sacks per dropback (9.3). His three touchdowns via scrambles tied for the most in the NFL.
Final QBR: 49.5
Final passer rating: 76.1
Analysis: In six starts for the Oakland Raiders, McGloin had the NFL's lowest completion percentage on third down (43.1). The rookie also was victim to the third-highest percentage of dropped passes (6.6).
Final QBR: 49.4
Final passer rating: 89.1
Analysis: Would you believe that Smith's 3,313 passing yards were a career high? So were his 308 completions and 508 attempts. Even so, the Kansas City Chiefs' offense was pretty conservative around him. He averaged the second-fewest air yards per attempt (6.54), and five of his touchdown passes and 454 of his yards came on screen passes. Those figures ranked No. 2 and No. 5 in the NFL, respectively. He also threw seven interceptions, giving him the third-best interception percentage (1.4) in the league.
Final QBR: 48.7
Final passer rating: 81.6
Analysis: Cassel did his best to separate his style from Ponder's, completing 45.7 percent of passes thrown at least 20 yards downfield. That figure ranked fourth in the NFL. But, for whatever reason, he was not accurate on play-action passes. His completion percentage of 52.1 percent on those throws was the NFL's worst.
Final QBR: 48.0
Final passer rating: 90.9
Analysis: In a seven-game stint, Bradford produced the best touchdown percentage (14 in 262 attempts), completion percentage (60.7) and yards per game (241) of his career. He also had his lowest interception percentage (four in 262) and had 7.3 percent of his passes dropped, tied for the most in the NFL.
Final QBR: 46.7
Final passer rating: 73.1
Analysis: Flacco seemed out of sorts in the Baltimore Ravens' offense, throwing 22 interceptions (10 more than his previous high) and taking a career-high 48 sacks. He ranked last in the NFL in completion percentage of passes thrown at least 15 yards downfield (27.8) and threw only three touchdowns on such passes. He threw five in the 2012 postseason alone.
Final QBR: 45.8
Final passer rating: 81.7
Analysis: Tannehill's total of 58 sacks was 10 more than the next-highest quarterback, and he completed only 31.9 percent of passes that traveled at least 15 yards downfield -- the third-lowest mark in the league. He did lead four fourth-quarter comebacks and had the second-most passing yards in the NFL against the blitz (1,521).
Final QBR: 45.6
Final passer rating: 83.9
Analysis: The Tampa Bay Buccaneers' offense was far from dynamic under Glennon, ranked last in the NFL with 6.27 yards per attempt and 5.04 yards per dropback. His receivers averaged 3.47 yards after the catch per completion, also the lowest for an NFL quarterback.
Final QBR: 42.3
Final passer rating: 77.7
Analysis: Manuel struggled in pressure situations, finishing with the NFL's second-lowest passing percentage on third downs (28.1). The rookie signal-caller also had the league's second-worst completion percentage against the blitz (48.2).
Final QBR: 40.1
Final passer rating: 82.2
Analysis: Griffin's ongoing knee recovery, as well as the Washington Redskins' offensive issues, exposed holes in Griffin's passing proficiency. He threw more passes (456) in 13 games this season than he did in 15 last year (393), but his completion percentage on downfield passes dropped notably. He hit 55.7 percent of passes that traveled at least 15 yards past the line of scrimmage in 2012 but only 40.7 this season, ranking No. 33 in the NFL.
Final QBR: 38.6
Final passer rating: 76.9
Analysis: Campbell kept it short and was best when inside the pocket in his stint as the Cleveland Browns' starter. His average of 6.36 yards per attempt was the second-lowest in the NFL. His QBR when outside the pocket was 2.4, the league's worst performance, mostly because he averaged 2.73 yards per attempt when throwing in those situations. Campbell also had the worst red zone completion percentage in the league (35.3).
Final QBR: 38.2
Final passer rating: 78.8
Analysis: The gap between Clemens' Total QBR at home (56.1) and on the road (16.5) was the largest negative differential in the league. Clemens also ranked last in the NFL with a QBR of 9.7 in the red zone.
Final QBR: 37.3
Final passer rating: 73.0
Analysis: Powered by pick-sixes in four consecutive games, Schaub threw more interceptions (14) than touchdowns (10) for the first time in his career. He had less success in play-action than any other NFL quarterback, averaging a league-low 4.95 yards per attempt on such throws and finishing with a 13.4 QBR in those situations.
Final QBR: 36.5
Final passer rating: 69.4
Analysis: In the same season, Manning set career highs in interceptions (27) and sacks (39) and a career low in touchdown passes (18) for a full season. His QBR in the fourth quarter (9.2) was the worst in the NFL.
Final QBR: 35.9
Final passer rating: 66.5
Analysis: Smith had his struggles this season, finishing with the NFL's second-highest interception percentage (4.7). He also completed only 59.7 percent of his passes when opponents sent four or fewer pass-rushers, the fifth-lowest in the NFL. But you might not realize that Smith had the NFL's second-best QBR over the final four weeks of the season (78.9). Only Peyton Manning's was higher over that stretch.
Final QBR: 34.5
Final passer rating: 78.2
Analysis: The blitz vexed Keenum in his eight starts, and he finished last in the NFL in completion percentage (46.5) and QBR (13.5) against it. His completion percentage in the fourth quarter (46.3) and overall (54.2) ranked as the second-worst among all quarterbacks. His best success came outside the pocket; he ranked second in yards per attempt (9.54) and yards/completion (19.55) in those instances.
Final QBR: 31.9
Final passer rating: 76.5
Analysis: How conservative was Henne in the Jacksonville Jaguars' offense? His average throw traveled 6.33 yards past the line of scrimmage, the lowest figure in the NFL. He also struggled outside the pocket, completing a league-low 31 percent of such throws, and had the second-worst QBR (12.3) on throws in the red zone.
Final QBR: 30.5
Final passer rating: 69.1
Analysis: As with many mobile quarterbacks, Pryor took a high number of sacks. His percentage per dropback (9.2) was the second-highest in the NFL, in part because he spent more time in the pocket (3.24 seconds) than any other quarterback. His completion percentage on third down (51.8) was worse than that of all league quarterbacks except McGloin.
Final QBR: 24.7
Final passer rating: 70.3
Analysis: Weeden's overall completion percentage of 52.8 ranked last in the NFL. He also converted a league-low 27.8 percent of his third-down attempts and had the second-fewest yards per dropback (5.31).
Final QBR: 19.4
Final passer rating: 85.7
Analysis: Flynn fumbled seven times in seven games, losing five. His QBR on first down (9.2) and against standard pressure (17.1) indicated a real struggle in passing efficiency in situations that lent themselves to better performances.
Jake Locker
Final QBR: 58.1
Final passer rating: 86.7
Analysis: Locker didn't play enough to qualify for QBR rankings, but he was an important part of the 2013 season, regardless. He had a QBR of 99.1 in the red zone, which would have led the NFL if he had qualified. He also completed just 25 percent of passes thrown at least 15 yards downfield. That figure would have ranked last in the NFL if he had qualified.