Mr. Irrelevant to Mr. Efficient: How Brock Purdy became NFL's all-time passer rating king

There is a new all-time passer rating leader in the NFL. A mere five years ago, nobody would have expected his name to be Brock Purdy.

The San Francisco 49ers quarterback was one pick away from going undrafted in 2022, and now he stands atop the career leaderboard for the ultimate signal-caller efficiency metric. Purdy threw his 1,500th pass in Monday's 23-17 win, which made him eligible for inclusion in the career passer rating standings and earned him a spot ahead of active surefire Hall of Famers like Lamar Jackson and Aaron Rodgers. He is also the all-time standard-bearer for success rate and adjusted yards per attempt.

Also in the Week 6 victory over the Washington Commanders, Purdy joined elite company with the third-most games with a 110 passer rating or better over the first five seasons of a career. Only Russell Wilson and Patrick Mahomes accumulated more, per Next Gen Stats.

All-time passer rating leaders

Purdy, a two-time QBR leader, is far from the most physically gifted quarterback in the NFL. But he leads all players in touchdown passes this year with 14 and accounted for the longest completion of the season thus far with an 82-yarder. He might be on his way to the MVP award. He has been the best player on the best team through six weeks, but his MVP case goes deeper than that; he is the primary reason why the 49ers are Super Bowl favorites.

Not bad for a "game manager."

Purdy shed that label — or perhaps instead perfected the art of game management — during his rise as one of the league's preeminent passers. The longer he plays like the most efficient quarterback in NFL history, the more he looks like a steal as the final pick of the 2022 draft. Purdy will always be known as a former "Mr. Irrelevant," but he is as relevant as anyone in football through six games in 2026.

That begs the question of how the 49ers pulled off the biggest steal of the 2022 draft. What did other teams miss in their evaluation of Purdy? What has San Francisco done to turn him into a star? How has he developed from a fringe prospect into an unstoppable passer?

Here is the formula behind Purdy's climb to excellence.

Elite mental processing

What Purdy lacks in stature as a 6-foot-1 quarterback and in physical tools, he makes up for with an uncanny ability to comprehend his offensive system and read defenses. That mental acuity has been the great equalizer between him and the more athletic quarterbacks, and it's arguably even given him a leg up on them.

"It's so important when it comes down to knowing coverages, knowing scheme, where our players are supposed to be, how many steps they're breaking and where the ball should be over a certain 'backer," Purdy said earlier in his career. "All those things, man, it matters. If you go to a combine and all those things, you're just throwing on air. Yeah, you look good with the strong arm and fast, jumping, all that stuff. But when it comes down to 11-on-11, and you've got guys that are a foot taller than you, and you can't see, it comes down to the processing."

That is precisely why Purdy thrives in the Kyle Shanahan offense.

The 49ers' system is designed to make life easy on the quarterback but only if he can process timing, anticipation and spatial awareness at a high level. All of the pre-snap motion in this offense not only confuses the defense but also requires the quarterback to comprehend how the defense will react. Purdy also has to recognize when a receiver will be open before he actually is. And the high rate of play action Shanahan calls forces Purdy to make quick decisions as defenders barrel toward him.

This week, Shanahan called Purdy "automatic" at running the system, which he said is the highest compliment he can give a quarterback.

There might not be a statistic more emblematic of Purdy's unmatched comprehension of the scheme than this: The Commanders on Monday blitzed him on 41.2% of his dropbacks (a season high), yet his 17.6% pressure rate was his second-lowest of the season. That speaks to his ability to make snap decisions. He gets the ball out of his hands quickly because he knows precisely where it needs to go. That will be on display again in Week 7 against an Atlanta Falcons defense that ranks second in pressure rate.

The 'Layer King'

Purdy is among the most accurate passers in the NFL and ranks second in career completion percentage for active quarterbacks at 68.1%. His propensity to put the ball on the money is most obvious when he layers his throws. 

The middle of the field is the most dangerous area in a Shanahan offense because of how linebackers and safeties tend to align themselves to stop it, yet Purdy is adept at picking that area apart with excellent touch on his passes.

49ers defensive coordinator Raheem Morris was bewildered by Purdy's ability to thread the ball through those tight windows in training camp and labeled him the "Layer King." Purdy pushed back on the moniker, but he explained to ESPN the art of weaving the ball over a linebacker just in time for his receiver to make the catch before the safety closes in.

"I think it's definitely one of the hardest throws on the field," Purdy said. "Those are things that I sort of prided myself on young ... Now in the NFL, I'm trying to take it to another level."

Just athletic enough

Purdy might not own the strongest arm, but it is potent enough to make all the throws asked of him. He is also arguably underrated as a runner. His oft-unsung quickness allows him to step up in the pocket and scramble to escape pressure laterally at an elite level. His sack avoidance metrics exemplify just how proficient Purdy is at frustrating opposing pass rushers.

The five sacks Purdy has taken in 2026 are the fewest of any quarterback. He also led the league in sacks taken per game last season (a more accurate measure than total sacks, since he missed eight regular-season games with turf toe) and ranked fourth in 2023.

Purdy averages a modest 156.6 rushing yards per season and will never rank alongside the more potent mobile quarterbacks like Josh Allen and Lamar Jackson, but his runs are effective, as his career rushing success rate of 56.3% shows. That is an above-average, albeit not elite, mark for a quarterback.

Legendary supporting cast

A lot of quarterbacks would succeed if they traded places with Purdy. His system and the stars around him are significant factors in his own accomplishments. That is not to take anything away from Purdy since, after all, he still needs to deliver the ball to his playmakers, but it does partially explain why someone with modest physical tools is able to produce at an MVP level. There are future Hall of Famers all over the San Francisco offense. Claiming that they are not a big part of Purdy's success would be disingenuous.

Christian McCaffrey, George Kittle and Trent Williams are all-time greats at their respective positions. McCaffrey and Kittle make the easy throws worth more than they might be in other offenses because of their tremendous yards-after-catch capabilities. Williams delivers some of the most reliable protection the NFL has to offer at left tackle. And this year in particular, Mike Evans has performed like arguably the most impactful free agent signee of the year.

Everyone in San Francisco makes everyone around them look better, and Purdy, with his incredible decision-making skills, perhaps elevates his offensive teammates as much as anyone.