In Part I of this series, I compared the passer rating to winning percentage for Tom Brady (aka the GOAT) over the past six seasons, and found that Brady’s team won significantly more often than league average, given Brady’s per game passer rating. Even when the GOAT had a bad game, which was more often than you might expect, his team won way more often than average. This suggests Brady’s team was a significant factor in winning football games, and could carry Brady to victory more often than Brady could himself.
In stark contrast, Kirk Cousins, who performed very similarly in terms of passer rating over the same period, was not carried by his team to victory in poor performances, and in fact had lower winning percentages at every passer rating level than Brady, suggesting Cousins’ team was highly dependent on Cousins having a great game for a good chance to win, and therefore being dependent on a QB to carry the team with a great game isn’t such a good thing.
In Part II, I’ll look at the relationship between quarterback performance and pass protection, reflected in the percentage of drop-backs a quarterback faces pressure, on a per game basis. Looking at the relationship on a per game basis isolates the impact of high, or low, pressure games on QB performance, and can be more insightful than season averages.
Great Quarterbacks Under Pressure
One of the things we’ve been conditioned to believe is that great quarterbacks operate well under pressure, often making spectacular plays with their elusiveness in the pocket. Today we see quarterbacks like Patrick Mahomes, Aaron Rodgers, and Russell Wilson work their magic by eluding rushers and working off-platform to make spectacular plays that make highlight reels. But looking more comprehensively at overall performance under pressure, a more mundane truth arises: ‘great’ quarterback performance comes largely from a relative lack of pressure, rather than their performance under pressure, particularly when looking at high pressure games.
Let’s begin by looking at who is generally considered the best quarterback in the league right now- Patrick Mahomes.
The scatter chart above represents Patrick Mahomes’ passer rating and pressure percentage rate for every game he started from 2018 through last season, with the associated trendline. As you can see, passer rating tends to decline as pressure rate increases - as expected with any quarterback.
What isn’t so typical is Mahomes’ pressure rate. The league average pressure rate per game last season was roughly 32%, meaning quarterbacks faced pressure an average of 32% of their drop-backs, whether sack, hit, or hurry, according to Pro Football Focus (PFF). That average can change a bit each season, but usually not much- just a percentage point or two. For Mahomes, he’s faced significantly above average pressure in just 9 of the 53 games he started since he took over in 2018. That’s only 17% of his total starts.
And while Mahomes didn’t always perform poorly when facing above average pressure, his record in those games is just 3-6 (.333). In games where he was pressured on over 40% of his drop-backs, he has yet to win a game- going 0-5 in those contests.
On the other hand, in his breakout MVP season of 2018, he faced pressure of over 30% just 3 times during the regular season- going 1-2 in those games. The other 13 games, his average pressure rate was only 19% - very low compared to league average.
Given Mahomes’ record in games when he faced above average pressure rates, which was put in more stark relief in his last Super Bowl performance, it’s no wonder the Chiefs approached rebuilding their offensive line with a great deal of urgency this off-season, having already made a 10-year, $450+ million commitment to Mahomes- the largest contract in NFL history.
It’s an open question whether Mahomes would’ve fared as well for a team without the level of pass protection Mahomes has enjoyed so far in Kansas City, and whether he would have been an MVP and Super Bowl MVP had he been drafted by the Bears, Jets, or Bengals, for instance.
Another question is whether the Chiefs can continue to afford to give him premium pass protection, as Mahomes’ salary cap hit increases dramatically in the next couple years- going from $7.5 million this year, to $35.8 million next year, and $46.8 million in 2023.
In any case, Mahomes has clearly benefited from well above-average pass protection over the last three seasons, and has led him to be one of the most successful quarterbacks in recent years.
Aaron Rodgers is another top-tier quarterback and reigning NFL MVP. As Vikings fans, we’ve seen all too often Rodgers elude pressure, roll out of the pocket, eyes downfield, ball in hand - it usually doesn’t end well. But for most of his career with the Packers, Rodgers has enjoyed above average pass protection, and sometimes the best in the league- like last season.
Above is the passer rating/pressure % scatter chart for Aaron Rodgers’ MVP season last year, in which he led the league in passer rating. He went 13-3 in the regular season, and 14-4 overall, including the postseason. You’ll notice that, just like Patrick Mahomes’ MVP season in 2018, Rodgers faced pressure of 30% or more in just 3 games, and only one of those did he face significantly above league average pressure. On the other hand, half of his games he faced very low pressure- 20% or less of his drop-backs, and all but four games he faced pressure of 25% or less- significantly below league average.
Now contrast Rodgers’ MVP season with his past three seasons overall:
Overall, this looks similar to Mahomes’ chart in terms of pressure rate, with only 8 games out of 52 significantly above the league average pressure rate, and only 5 above a 40% pressure rate, while 16 games Rodgers faced very low pressure- 20% or less. Overall, Rodgers’ passer rating in largely similar circumstances in terms of pressure rate trended lower than Mahomes, but still very favorable conditions for a quarterback to operate in terms of pressure rates faced compared to league average.
While both Rodgers and Mahomes enjoyed favorable pressure rates most games over the past three seasons, Tom Brady enjoyed perhaps the most favorable of any quarterback in the league over the same stretch - winning two Super Bowls in the process despite a notably lower passer rating trend line. To compare trendlines, look at where the trendline intersects with the 30% pressure rate line, along with the slope of the trendline (which is similar).
As you can see from Brady’s scatter chart, he faced very low pressure rates in nearly half of the games he played over the past three years- and only a handful of high pressure games. Moreover, Brady faced pressure over 30% in just 13 games over three seasons.
Brady’s trendline is significantly lower than Mahomes and Rodgers, however, suggesting he wasn’t able to use those favorable conditions to his advantage as well as Mahomes and Rodgers. But overall, Brady - like Mahomes and Rodgers - enjoyed the advantages of very good pass protection over the past three seasons, which led to their success.
Not every quarterback has enjoyed the same situation as Tom Brady. Deshaun Watson is generally considered a top-tier quarterback, and is paid like one, despite having a winning percentage and playoff record much more similar to that other kind of goat - Kirk Cousins.
One of the reasons for his Cousins-like winning percentage and playoff record may be that the pressure rate he’s faced is also similar to... Kirk Cousins’.
Watson’s scatter chart is roughly the mirror image of Brady’s or Rodgers’, or Mahomes, with roughly the same amount of high pressure games as the other top-tier quarterback’s low-pressure games, and about the same number of low-pressure games as the other QB’s high pressure games. And yet Watson’s passer rating over the same period was about the same as Aaron Rodgers’. Better than Brady’s, and a bit lower than Mahomes’.
But Watson generally has some of the same issues that Cousins’ detractors cite for him: can’t deliver wins, can’t beat good teams, can’t win a Super Bowl. Sure he’s got some good stats, but not much to show for it.
For comparison, here is Kirk Cousins’ scatter chart:
Like Watson, Cousins has faced a lot more high pressure games than low pressure ones, and like Watson, Cousins didn’t always do poorly in high pressure games. But at the end of the day, facing more pressure is akin to swimming against the current rather than with it, and it’s difficult to win as many races that way.
Finally, among top-tier quarterbacks, there is Russell Wilson. His scatter chart represents something of a middle ground between Mahomes/Rodgers and Watson:
Wilson’s pressure rate is something close to league average over the past three seasons, with a roughly equal number of high- and low-pressure games, and many very close to the league average pressure rate. His trendline is also pretty similar to Mahomes, Rodgers, Watson and Cousins, but his pressure rate bridges the gap between the first two and the latter two, with his regular season winning percentage close to Rodgers’, and his playoff wins (1), similar to Rodgers (2), Watson and Cousins (1).
Overall, the ultimate success of each quarterback during this period aligns more closely to their pressure rate than their passer rating, with Brady having the lowest pressure rate (but also lowest passer rating) and the most championships over this three year period. That suggests that ultimately it’s the quarterback’s team, or in this case his pass protection, that made the difference, rather than the quarterback himself - even those of the top-tier variety.
While it’s true that top-tier quarterbacks depend on their pass protection for success, it’s an over-simplification to say that any garden-variety quarterback can succeed with good pass protection. The top-tier quarterbacks stand-out as such because they tend to do better than others at any given level of pressure, although they’re still dependent on good pass protection when it comes to winning and championship runs.
Baker Mayfield is an excellent example of a quarterback afforded excellent pass protection- right up there with Tom Brady for the best in the league - but hasn’t been able to do as much with that advantage.
Mayfield’s scatter chart looks a lot like Tom Brady’s - very few high pressure games and lots of low-pressure ones. But notice the trendline and where it intersects with the 30% pressure rate line. Mayfield’s intersects just above an 80 passer rating, while the top-tier quarterback’s (except Brady) intersect above 100 - 20 points higher than Mayfield. That suggests Mayfield is missing something top-tier quarterbacks possess.
Another interesting example of quarterback performance and pass protection is Ryan Tannehill. He was basically a mid-tier journeyman quarterback with Miami for his first several years in the league before moving to Tennessee the last couple seasons. Miami was not a good team while Tannehill was there, and his move to Tennessee represented an upgrade of the team around him, including pass protection.
Above is Tannehill’s scatter chart his last couple seasons in Miami (Tannehill didn’t play in 2017). A fairly random scatter chart in many ways, but notice the number of games near or above a 40% pressure rate. He was a basically about a 90 passer rating QB over his tenure with the Dolphins, and jumped to a 110 passer rating QB with the Titans.
Comparing Tannehill’s scatter charts, it’s not too difficult to see why his passer rating improved 20 points in Tennessee. He went from having a majority of games with 30% or more pressure, including quite a few near 40% or above, to having only a handful of games with more than 30% pressure. That’s a big change in pass protection.
Tannehill also became a more consistent performer in Tennessee, compared to his more random performance his last couple seasons in Miami. But while his overall trendline did improve slightly with his move to Tennessee, suggesting some general improvement outside of pass protection, the majority of Tannehill’s improvement came simply from better pass protection and moving up the slope on his trendline.
Tannehill is generally considered a second-tier quarterback since his performance in Tennessee, but statistically he is comparable with the top-tier quarterbacks today. That’s a big improvement over the mid-tier guy he was in Miami. It will be interesting to see how the addition of Julio Jones impacts his performance going forward as well.
While it’s an established fact that quarterback performance is dependent and influenced by his level of pass protection, we don’t often see it that way when looking at particular quarterbacks. Instead we tend to remember highlights reels of quarterbacks that have won a lot of games and assign them super-human qualities, when in fact their performance is very much a product of the premium pass protection afforded them.
For less winning quarterbacks, we often look at shortcomings: failing to deliver in key moments- moments when pass protection is often challenged the most. And from this we judge that they just don’t have that special something the top-tier quarterbacks have. And while there are certainly differences in quarterback ability, there are more quarterbacks than those currently in the top-tier that could likely produce just as well given a better team, and particularly better pass protection, around them. By the same token, the winningest among the top-tier quarterbacks today might not have enjoyed nearly the success they have in recent years had they been made to suffer league-average or worse pass protection.
In Part III of this series, I’ll take a look at the impact of other parts of the team on quarterback performance- and ‘greatness’ - including a look back historically at some of the great quarterbacks in the Super Bowl era and the team around them.