It isn’t an NFL season if the San Francisco 49ers aren’t enduring terrible injuries and Kyle Shanahan isn’t doing some wizardry at the quarterback position. On that note, the 2022 NFL season is officially underway, as once-starter-then-backup-then-starter-again quarterback Jimmy Garoppolo sustained a foot injury in the 49ers’ Week 13 game against the Miami Dolphins, prompting Shanahan to turn to rookie seventh-round pick Brock Purdy, who promptly threw for 210 yards and two touchdowns to earn the win for San Francisco.
Purdy will start for the 49ers for the foreseeable future (Shanahan said this week that the idea of Garoppolo returning late in the postseason has only “an outside chance” of happening). That foreseeable future is an important one. The 8-4 49ers are only one game ahead of the Seattle Seahawks—who they’ll face next week, after Purdy’s first career start this week against the Tampa Bay Buccaneers.
Purdy’s status as the Niners’ starter resurrects an old debate surrounding the San Francisco offense under Shanahan and in the era of Garoppolo. We all know that elite quarterbacks are irreplaceable—Case Keenum cannot replicate what Josh Allen does for the Bills, nor Chase Daniel for Justin Herbert or Chad Henne for Patrick Mahomes. But just how replaceable is a quarterback like Garoppolo? As a former second-round pick without elite size, arm strength, or creativity, Garoppolo is often cast as the product of Shanahan’s magic, not the author of his own successes. This idea is the key to understanding why the 49ers spent multiple first-round picks in an aggressive trade for Trey Lance, an extremely young, extremely raw, but extremely gifted quarterback who they envisioned eventually supplanting Garoppolo as the starter.
Lance didn’t unseat Garoppolo last season, and was given the starting job this season even as the team failed to trade Garoppolo away. But Lance was hurt in Week 2, forcing Garoppolo back into the starting role—and Garoppolo grabbed the bull by the horns. This was perhaps the best football we’ve seen Garoppolo play in his career. He has been a play-action merchant for most of his career, but this season, Shanahan has used play-action on fewer than 30 percent of Garoppolo’s early-down dropbacks—the lowest number for Garoppolo since 2017. Similarly, Garoppolo has never been in shotgun on early downs more than he has this season. The prototypical Shanahan offense—defined by a heavy use of under-center, play-action dropbacks—has been phased out.
Some tenets of the offense remain. Garoppolo still leads the league in the percentage of his yards that come after the catch. He’s still got a low time to throw, a stat that perennially highlights Garoppolo’s rapid release and Shanahan’s strength as a designer of the quick game. These facets remain because they play into the strength of the receivers—any offense featuring Deebo Samuel, Brandon Aiyuk, and Christian McCaffrey will be among the league’s best in yards generated after the catch—and because they play into Garoppolo’s strengths. But the training wheels of the offense have been knocked off of Garoppolo’s bike. He’s a big kid now—or, at the very least, Shanahan trusts him as one.
That Garoppolo was playing such mature ball makes his injury all the more disappointing. This 2022 offense was arguably the best one Shanahan had put together in San Francisco, maybe good enough to avoid faltering in the postseason like the 2019 and 2021 teams did. Instead, Shanahan will now be asked to do exactly what he once did with Garoppolo: elevate a quarterback to generate an offense beyond his skill level. This time, that quarterback is Purdy.
Shanahan has been in this spot before. Garoppolo tore his ACL in Week 3 of the 2018 season, forcing backup C.J. Beathard into the starting role. Beathard, who had started five games the season prior when filling in for the benched Brian Hoyer, came from an under-center, play-action offense in college and had the pro-style sensibilities a Shanahan quarterback needed. (Remember, this was the time in quarterback drafting and development when everyone in the NFL was terrified that shotgun snaps were ruining quarterbacks, and that no college passers could capably learn how to take an under-center dropback.)
But Beathard’s experience in the offense didn’t translate to NFL success. Shanahan used play-action on 24 percent of Beathard’s attempts—a number equal to what he’d given Jimmy in 2017. And while Beathard was a viable quarterback on those play-action attempts, he was dreadful on attempts without play-action. Beathard had one of the lowest times to throw (2.41 seconds) and one of the lowest completion percentages (57.5 percent) among quarterbacks that season. He was a quick-game quarterback who couldn’t complete passes.
Then Beathard himself went down with injury in Week 8, forcing an undrafted free-agent rookie third-stringer (which is, objectively, the only player lower on the totem pole than a Mr. Irrelevant rookie third-stringer), Nick Mullens, into the starting lineup.
Mullens was better for the 49ers than Beathard was. Mullens also got the play-action boost, as all Shanahan quarterbacks do—but on standard dropbacks, he was much more useful. He got rid of the ball even faster (2.36 seconds to throw) and completed an acceptable number of passes (64 percent). Mullens looked a lot more like Garoppolo does on standard dropbacks—high completion percentage, low time to throw, low depth of target.
The 2018 Mullens stretch was Shanahan’s first brush at creating an offense with a third-string quarterback in San Francisco, and unsurprisingly, he used the same crutches his offense has always deployed—the same crutches that he had used in small doses with Garoppolo, whom he had acquired midseason in 2017. As The Ringer’s Steven Ruiz wrote back when he was with For the Win, all but one of Mullens’s dropbacks in his first game as a starter—a 262-yard, three-touchdown, 31-point win—came with a play-action fake or pre-snap motion. Training wheels offense. But despite his lucky place as the quarterback helming the Shanahan offense, Mullens didn’t soar to heights previously undiscovered. During his San Francisco career, Mullens produced remarkably worse numbers than Garoppolo.
The training wheels offense minimizes the importance of the quarterback and asks the skill position players to carry the load—it needs athletes who can create after the catch. Someone has to do the heavy lifting. But the 49ers’ skill position group obviously wasn’t then what it is now. In 2018, during Mullens’s and Beathard’s first stints as starters for Shanahan, the 49ers had a young George Kittle in hand, but their starting wide receiver corps featured Kendrick Bourne, Dante Pettis, and Marquise Goodwin. Matt Breida was the primary back, until he was replaced by Jeff Wilson Jr. Later, in 2020, when Garoppolo sustained new injuries, and Mullens and Beathard were both back in the lineup, Brandon Aiyuk had been drafted, but Kittle and Samuel were in and out of the lineup with injuries of their own. As Kevin Cole wrote this week, Mullens’s numbers in this offense are better than Garoppolo’s only when both Samuel and Kittle are available—when one or both were off the field, Garoppolo’s offenses did far better.
These phenomena make the overall thesis—that Shanahan’s offense elevates quarterbacks, and accordingly, can work with Purdy at the helm—difficult to parse. A player like Beathard couldn’t execute the offense at all—he just wasn’t quick enough in the pocket, nor accurate enough as a passer—while a player like Mullens could do similar things to Jimmy, just only when the training wheels were on. Yet this season’s offense has largely not used the training wheels! So where does that leave Purdy?
Firstly, Shanahan has a player in Purdy who looks far more like Mullens than he does Beathard. Purdy, like Mullens, is an undersized, quick-release quarterback who has the accuracy and toughness to make the throws this offense requires. This week, Shanahan highlighted both Purdy’s “aggressive[ness]” and willingness “to play fast” as the strengths that he will bring to the offense—and what he will highlight as the play caller. Those are the sorts of traits that make plays like this possible.
While Mullens initially inherited a Shanahan offense already squeezing as much as it could out of Bourne and Pettis, Purdy lands in an offense that has more mismatch-creating pass catchers than any other team. Samuel and Kittle are the names that everyone knows, but Aiyuk is having a career year, and has been the most dangerous of the three this season. And, of course, Christian McCaffrey is the league’s best pass-catching back, and perhaps the best safety blanket a quarterback could ask for.
The cumulative talent of the skill players contributes to the diminished amount of under-center play-action in this year’s iteration of the Shanahan offense. The training wheels offense minimizes the responsibility of the quarterback and asks the pass catchers to do work after the catch—but it has its drawbacks. The pass concepts are pretty simple. The condensed passing sets make it easier for defenses to disguise coverages and send blitzers. The under-center, play-action fakes force the quarterback to turn his back to the play, giving the opposing defense a split second to change the picture.
The 49ers haven’t needed to leave the training wheels on for two reasons: first, because Garoppolo doesn’t need them anymore; second, because the skill position players are just so good. An offense with Samuel, Aiyuk, Kittle, and McCaffrey doesn’t need much more than a spread formation, a little window dressing, and a quarterback willing to trust his receiver to win a matchup. The 49ers passing game has been good this year because Garoppolo’s been better, yes—and because Shanahan is so very good, yes—but also because Deebo and Aiyuk and Kittle and McCaffrey are all just better than the guys lining up across from them.
One piece of that puzzle is gone now—Garoppolo’s out, Purdy’s in. But there’s reason for more faith in this third-string quarterback as opposed to the other Shanahan backups and their fraught tenures. Purdy isn’t entering an offense that needs training wheels to produce—that means that Shanahan can deploy the training wheels for him to lean on. Twenty-five percent of Purdy’s dropbacks came with play-action last week, per TruMedia; Garoppolo has exceeded that single-game number in only two outings this year. Faith in Purdy isn’t about what we’ve seen Shanahan do with Beathard or Mullens—it’s about what we’ve seen Shanahan do in several seasons, as Garoppolo developed into a solid performer and a second-round receiver and a fifth-round tight end developed into star pieces. It’s about a very good offensive coach who has regularly created something out of nothing, across many different positions and many different seasons, and a quarterback who should have just enough skills to scrape by.
It’s not going to be as good—that’s what happens when an important, solid player leaves an offense. The 49ers aren’t hoping to get a Garoppolo out of Purdy—they’re hoping to get a Mullens. But they can get that. They have enough skill position power and an extraordinarily gifted head coach. And with that—with a quarterback who can scrape by, and an offense that can elevate him, and a defense that can dominate in the mean time … who knows? The same old 49ers—that excellent defense, that irritating offense, and that genius at head coach—might make yet another playoff run.