The Purdy Problem
On building a contender, the NFL's Quarterback Arms Race, and why the 49ers are uniquely positioned to challenge the status quo
Brock Purdy, who not long ago was San Francisco’s Mr. Irrelevant, is now in line for a $60M per year extension - and by the league’s standards for a franchise quarterback, he’s earned it. In his two-and-a-half seasons starting, Purdy has led his team to appearances in the NFC Championship and the Super Bowl, all while posting statistics that rank amongst the league’s best quarterbacks.
But the 49ers’ 6-11 2024 season has complicated the case for Purdy's mega-extension. Injuries to key playmakers like running back Christian McCaffrey, receivers Brandon Aiyuk and Deebo Samuel, and left tackle Trent Williams stalled out the offense - and Purdy along with it. The limitations of his game began to show: the mistakes crept up, the accuracy dropped off, and the big plays did, too. Purdy’s regression without the full complement of weapons is perfectly reasonable, even for a good quarterback, but it also illustrates a key point that was harder to observe when the Niners' offense was rolling: Purdy’s success is deeply dependent on the weapons around him, to a greater degree than the NFL’s truly elite quarterbacks.
The tension for San Francisco is that Purdy’s contract will likely command around 20% of the salary cap, permanently reducing the number of offensive weapons he’ll have going forward. San Francisco currently has the best group of playmakers in the league, with Williams, Aiyuk, Samuel, McCaffrey, tight end George Kittle, and fullback Kyle Juszczyk all amongst the best and highest-earning players at their position. That is an ensemble you can employ when your quarterback is making his current salary of $985K, less than .4% of the cap, but not when that number jumps above 20%. In the long-term, securing Purdy’s future in San Francisco also means breaking up the band.
Unless, of course, San Francisco chooses not to pay Purdy. Because if this season has offered the Niners a preview, if extreme, of what life will look like with Purdy leading an offense with fewer elite weapons, it’s worth wondering if that’s a future worth locking themselves into. The league has continued to accept as conventional wisdom that a quarterback contract worth 20% of the salary cap is table stakes for competing, even if that quarterback isn’t a transcendent talent. But the 49ers, whose quarterback-whispering head coach and elite cast of playmakers laid the ground for Purdy’s breakthrough in the first place, might also be uniquely positioned to let him go.
Why Pay Anyone 20% of the Salary Cap?
There is a reason the market has driven the price of a franchise quarterback to 20% of the cap. Quarterbacks have more impact on their team’s success than any other position. They produce the most yards, touchdowns, and turnovers - all the ingredients that win or lose you a game. It’s no coincidence that Patrick Mahomes and Tom Brady, widely considered the two best quarterbacks in league history, have accounted for seven of the last ten championships. Couple this with the fact that quarterbacks have a longer prime than other positions, and securing a high-level quarterback becomes the most obvious way to help your team become a contender over the long term.
Of course, these factors also make quality quarterbacks the scarcest and most expensive assets in the NFL. That has been true for a long time, but in recent years, the NFL’s passing revolution and more quarterback-centric schemes have sent the quarterback market into overdrive. In 2011, when hall-of-famer Peyton Manning signed his market-setting deal, it was for around 15% of the salary cap. Across the last five seasons, the market-setting quarterback contract has been for at least 22% of the cap.
But what has also defined this era of quarterback-centric team-building is that it isn’t just the league’s very best quarterbacks getting these top-of-market deals. Today, the NFL has 15 quarterbacks making over $40M/year, representing nearly half the league’s franchises. How each of those teams got there is also remarkably similar. Generally, they endure a losing season that lands them at the top of the draft, where they spend a premium first-round pick on a rookie quarterback. Those young quarterbacks play on discounted rookie contracts for their first three seasons while they develop. If they look “franchise-worthy” by year four, when they become eligible for an extension, they get a contract worth around 20% of the cap.
This is the process nearly every team with an elite quarterback has followed, and it has become the platonic ideal of team-building. Yet, as more teams converge on this strategy, some strange market effects have emerged. The cost of securing a franchise quarterback has gone up, but the bar for what qualifies as one hasn’t kept pace. As a result, teams get wildly different values out of their 20% investment. Compounding those problems is that the quarterback market seems tied to a percentage of the salary cap, which increases yearly with league revenues, meaning that the cost of a good quarterback today is often more than an elite one from a couple of seasons before.
Suppose you define the value generated by each quarterback as EPA, or expected points added. In 2024, the Bills put 17% of the cap into Josh Allen and got a league-leading 206 EPA out. The Cardinals allocated 18.5% to Kyler Murray and only got 89.5 EPA. For reference, the Bills had an overall point differential of 157 this season, and the Cardinals’ point differential was 21 - meaning the difference between the #2 seed, 13-4 Bills, and the playoff-less 8-9 Cardinals was almost exactly the difference between Allen and the higher-paid Murray. The Cardinals, however, could have done much worse than Murray’s deal. Trevor Lawrence is eating up 4% more cap space than Murray and posted half as much EPA on a per-play basis. Dak Prescott is making a league-high 23.5% of the cap, but before his season-ending injury, he produced .018 EPA-per-play, 1/8th of Murray’s production and 1/16th of Allen’s.
Now, looking at quarterback output like this is a slight oversimplification in that we aren’t considering the schemes these quarterbacks are operating in or the state of the team around them. This analysis also doesn’t consider that NFL GMs have avenues to distort the cap hit of quarterbacks each season, like adding void years to stretch it over a longer period. But broadly, this is the state of the NFL quarterback market today: more teams are signing their quarterbacks to an increasingly large percentage of the cap and are getting massively different output from those investments.
The consequence of signing your quarterback to one of these mega-deals is that it means having to cut back on talent across the roster. If 20% of the salary cap goes to one player, that means there is only 80% to pay the other 52. If you have Allen or Mahomes, who in a “down year” is still putting up a ton of EPA, you can do that and still be one of the league’s best teams. The less value you get from that 20% investment, though, the harder it gets to compete. While this list has most of the league’s contenders on it, it also contains several cautionary tales as well. The Cowboys and Jaguars gave Dak Prescott and Trevor Lawrence, respectively, market-setting deals and saw their offenses stall with fewer playmakers. Joe Burrow’s offense in Cincinnati has been excellent, but the budget defense they use to balance the books has been hemorrhaging points faster than he can score them.
For teams who draft a “fringe franchise” option - players like Prescott, Lawrence, or Tua Tagovailoa - it’s worth asking what the path to winning the Super Bowl is after one of these deals. The market dictates that teams pay these solid quarterbacks the same as superhumans like Allen, Mahomes, and Lamar Jackson, but they get much less production at the same 20% of the cap. With their roster depleted by their quarterback's mega-contract, they then have to beat three or four of those superior quarterbacks in the playoffs to win the Super Bowl. For many teams, today’s team-building paradigm means joining a quarterback arms they are not equipped to actually win.
It continues to happen, however, due to the uncertainty of the alternatives. Quarterback is still the most impactful position in the league, so you need to generate stable output from the position to win. Suppose teams let the fringe franchise quarterbacks go, either via trade or free agency. In that case, their options are either the draft, where each quarterback is a complete unknown1, or fielding a quarterback that another team has already discarded, something we’ve established doesn’t happen for many suitable options in today’s NFL.
But would your team be more willing to risk the quarterback wilderness if you had a playcaller who has gotten solid production out of just about every quarterback he’s ever coached? As San Francisco weighs whether Purdy is worthy of a franchise deal, they’ll be doing it knowing their head coach, Kyle Shanahan, has achieved more with less at quarterback than perhaps any play-caller in the league.
The Power of Play-calling?
Kyle Shanahan’s play-calling career started as an offensive coordinator in Houston, where he helped quarterback Matt Schaub, who to that point had been a replacement level option, lead the league in yards on his way to his first Pro Bowl. Shanahan repeated that trick as an offensive coordinator in Washington, where he was the architect of Robert Griffin III’s debut season, which earned him Offensive Rookie of the Year and a Pro Bowl nod. Following a down year with the Browns (even Shanahan couldn’t save the Browns at quarterback), Shanahan was the play-caller for Matt Ryan’s 2016 MVP season with the Atlanta Falcons, which earned Shanahan the head coaching job in San Francisco. Former Patriots backup Jimmy Garoppolo thrived in Shanahan’s system before an injury led to Brock Purdy, the last pick in the 2022 draft, taking over midway through his rookie season.
What fundamentally sets Kyle Shanahan apart as a play-caller - from both the league as a whole and his father Mike’s much-imitated “Shanahan System” - is how Kyle uses his creativity to get the most out of his playmakers. Shanahan is a master at leveraging the specific talents of receivers, running backs, tight ends, and even fullbacks. As Ben Solak covers in his piece about Shanahan at The Ringer, Shanahan’s offenses aren’t built around a particular type of play. Instead, the offense relies on having credible threats at multiple positions and finding different ways to disguise and combine those threats to punish a defense. In other words, in a quarterback-centric league, Shanahan runs an offensive system that is pointedly playmaker-centric.
While the playmaker-centricity of the offense doesn’t diminish the quarterback’s importance, it does simplify his role. When executed well, and Shanahan nearly always executes well, it makes the game more predictable, getting playmakers open at the right time in the right place.
This tasks the quarterback with making lots of on-time, on-target throws to open playmakers. Those throws are valuable in every offense, but the dynamism and flexibility of Shanahan’s offenses tend to create more “system” throws for its quarterbacks, reducing the number of plays that break down and force the quarterback to create on his own.
Crucially, that also means that players without the special abilities we typically associate with franchise quarterbacks, like Mahomes’s improvisation skills or Josh Allen’s arm talent, are still able to thrive within the Shanahan System if they have strong “system” abilities like working through progressions, reading defenses, and maintaining the timing and rhythm of the play. It’s in these “system” skills that Brock Purdy excels and helps explain why he was able to slide into the starting role as the draft’s last overall pick and produce elite numbers. Part of the reason Purdy fell in the draft is because he lacks the size or arm talent of traditional franchise quarterbacks (although he has proven to be a surprisingly solid improviser), but Shanahan’s play-calling minimizes those deficiencies while maximizing his “system” skills.
Yet, it’s also Purdy’s excellence in these “system” traits, and his relative lack of “franchise” traits, that makes the prospect of extending Purdy a problem. If San Francisco allocates 20%+ of the cap to him, they will reduce the number of playmakers at Shanahan’s disposal. That reduces the combinations Shanahan has to get those weapons open and, in turn, the effectiveness of the offense, putting Purdy in more positions where he needs to use those superhuman qualities that he lacks.
That line of reasoning, along with Shanahan’s track record of getting solid play out of almost every quarterback he’s ever coached, sets up a provocative question: Is it better for the 49ers’ future Super Bowl chances to double down on the playmakers that power the system rather than the quarterback operating it? If Shanahan can conjure high-level quarterback play without paying an elite option at quarterback, it opens up countless roster-building possibilities for the 49ers. The difference between a $30M/year quarterback (what Baker Mayfield or Geno Smith are making today) and a $60M/year option is enough to transform a roster - it could buy a top-5 wide receiver or multiple top-20 playmakers, anchor an offensive or defensive line, or field a top-notch secondary. Rather than strip the talent out of the roster to be constructed like the rest of the league’s contenders, the 49ers can double down on the strategy that has made them a perennial contender, like two seasons ago when they paid Purdy .4% of the cap and fielded six current or former All-pros on offense and four on defense2.
A Playmaker-Centric Proof of Concept?
I think it’s more likely than not the 49ers will give Purdy his mega-deal. There are a lot of factors beyond the likelihood of winning a Super Bowl that play into the decision. In a past piece, I discussed the principal-agent problem, where NFL GMs face incentives that put their job security at odds with the team’s best chance of winning a Super Bowl. Shanahan, along with GM John Lynch, would be under intense scrutiny if they bucked convention and let Purdy walk.
If they did let him go, however, they would not be totally without company. Last offseason, Minnesota opted not to match a $45M/year offer for their quarterback, Kirk Cousins. Instead, they drafted rookie J.J McCarthy and signed Sam Darnold to a one-year, $5M deal as they prepared to rebuild. But despite expectations, Vikings won 14 games in the 2024 regular season, and Darnold earned a Pro Bowl nod. With the money they saved at quarterback, the Vikings supplied Darnold with some of the league’s best playmakers, headlined by Justin Jefferson, Aaron Jones, and Jordan Addison. Running the show is head coach Kevin O’Connell, another of the league’s premier play-callers and a branch off the Shanahan coaching tree via Sean McVay. If you don’t buy into the idea that Darnold went from one of the league’s biggest busts to a high-end quarterback overnight, then what you see in Minnesota might be a non-quarterback-centric proof of concept: a top play-caller with top playmakers competing for a Super Bowl with a budget option at quarterback.
For many teams in the league, those without the playmakers or play-callers of San Francisco or Minnesota, maybe signing Purdy or Cousins really is the best choice. But for these organizations that have spent years cultivating success by thinking differently, and who have the tools and talent to challenge the quarterback-centric orthodoxy, playing the same roster-building game as the rest of the league might be riskier than the unknown.
Edited Excellently by Greta Gruber
Offense: McCaffrey, Aiyuk, Samuel, Williams, and Juszczyk. Defense: Nick Bosa, Charvarius Ward, Talonoa Hufanga, Fred Warner. The Niners actually had 5 current/former All-Pros on defense this season, but the fifth was De’vondre Campbell, who is not a fan favorite in San Francisco.
One of the issues with Joe Burrow is that the bengals scouting department has woefully underperformed (and is underfunded). Is there actual data correlating scouting payroll / draft hits with quarterback EPA?
it hurts my brain thinking about how much QB salaries have ballooned in the past decade. At this rate, there will be a $100mil/year QB soon, which seems insane.
that said Alex, I feel like it was known that Tom Brady would take a lesser salary to keep a better roster around. Do you know of any other star QB's who have done that?