Film room: reassessing what happened on Purdy's injury. Was it bad play design or bad luck?
Today we'll look at the infamous play that set up Brock Purdy for offseason elbow surgery and put his 2023 season in serious jeopardy.
In late February, national media reported that Brock Purdy is going to delay having surgery on his elbow because of persistent inflammation at the injury site, potentially delaying his return to action until sometime well into the preseason and jeopardizing his status for week 1 of the 2023 season.
He surgery was scheduled for yesterday in Texas provided the swelling had gone down enough for his doctor, the Texas Rangers team physician, to operate on him and determine what repair needs to be done, either Tommy John surgery, or a ligament brace, or a hybrid of the two.
The surgery is complete and he ended up having the internal brace attached to his ligament. He’ll miss the offseason program and could be cleared to throw in three months on a strict rehab program with full clearance maybe 6 months away, which wouldn’t be until after the end of preseason. There’s a chance he won’t be ready to reassume the starting role.
I have resisted giving this a second thought or writing about it because I don’t know what I could say that hasn’t already been said by me online on Twitter and by everyone else who’s covered it but I figured it’s a good opportunity to show why Brock Purdy’s injury is no one’s individual fault but is rather just bad luck and a learning experience for everyone involved. There really isn’t one specific thing that could’ve been done to mitigate the injury or prevent it from happening.
49ers recent play action scheme calls
The style of play call is as common to the Shanahan offense as it is to every other offense in the NFL. It occurred on the 6th play from scrimmage in the NFC Championship game on an under center play action pass that had him taking a deep drop to give the primary and secondary reads time to develop downfield.
The play call is likely “Pass 18/19 Willie X Read Out Y Locker.” The play call isn’t as important as what the 49ers are trying to do with the pass concept and that is using it as a change-up to a play action pass they put on tape versus Seattle in the wildcard round about a handful of times.
Shanahan is known for creative designs and game plan specific adjustments to his base play calls depending on the opponent. Versus Seattle in the wildcard round, Shanahan adjusted his plays based on Seattle’s defensive structure and knowing how their underneath defenders distribute versus the pass on deep crossing routes.
The play call is designed to put the coverage defenders underneath in a bind by basically taking advantage of their coverage rules for covering crossing routes. Typically, the routes on this play would be flipped with the dig/crosser coming from the left and the corner coming from the right.
Shanahan knows that when this happens, the linebackers will “robot” (roll over and back) to locate the crossing route. If they see zone run action one way, they will “roll over” their back shoulder and turn to locate the crossing route from that side of the formation. Knowing this, Shanahan flipped the routes to put the underneath defenders in a bind when they couldn’t find the crossing route.
With how the Seahawks distribute their zones, the strong hook and flat defenders also have to keep eyes on the flat and checkdown routes. This leaves a void in the middle of the intermediate areas of the field.
Seattle doesn’t chase the run so aggressively and linebacker Cody Barton zones off into coverage where he “robots” looking for the crosser behind him from left to right but doesn’t locate it and sees Aiyuk running from right to left on the dig. Purdy waits a half second longer until Aiyuk clears into the next window before throwing it over the middle.
The 49ers ran this play on at least 3 separate occasions versus Seattle.
The injury play vs Philly
On the play versus the Eagles in the NFC Championship game, the 49ers called this play action pass concept for two reasons: 1) it was a change up to the play above with Aiyuk running a blaze out instead of a dig. He would sell the same stem, get the defender to jump inside, and then cut outside. 2) The Eagles corners were likely coached or had it in their game plan to jump inside and cut the dig route to prevent free access across the field on an explosive pass play.
Shanahan correctly assumed the defensive backs would drive on everything breaking inside and this appeared to be a good answer for the Eagles game plan.
The 49ers are running this play from a YY nub formation with two tight ends to the right. Kittle, as the inside tight end, is running the deep dig route over the middle, the “locker” route. Tight end Tyler Kroft is the outside tight end and is tasked with first pass blocking the defensive end Haason Reddick long enough to buy Purdy time to throw and second releasing as a checkdown option.
Kroft actually blocks this decently well and holds off Reddick long enough for Purdy to throw. Where he went wrong is I think he expected to hold off Reddick a half second longer and when Reddick shed the block, Kroft tried to stay with it as best as he could but got his feet crossed up and couldn’t hang in there long enough.
It might not have mattered if Purdy threw the ball with some anticipation or timing and one thing Shanahan could’ve done to mitigate the rush on his end was design the route to be broken off a couple of yards sooner on a slower developing play. Either way, this is a pretty standard play action concept with standard responsibilities.
But Rich, you might be asking, why would you put a backup tight end out on the edge to block one of the best pass rushers in the league??
Because lots of teams blocked Reddick with a second or third tight end this season and didn’t suffer the same consequences. Not doing what Shanahan did in the game plan would mean abandoning their bread and butter concepts, ones they’ve run all season like that with Kroft and Charlie Woerner. And for the 49ers to have success in the run game and play action pass game, they need to make everything look the same and tight ends regularly block the opposing teams best pass rushers in the run game.
And lots of teams didn’t suffer the same consequences as the 49ers. A cursory watch through of some of the Eagles other opponents shows that other teams did in fact block Reddick with a backup tight end on numerous occasions.
The Chiefs also did it with their backups a couple of times and their pass protection was arguably worse this season than the 49ers.
The Eagles also generated a 41% (11 on 27 drop backs) pressure rate on Mahomes in the Super Bowl. Reddick and everyone else were getting home, when they could find their footing on the turf, but Mahomes has some of the best pocket presence in the league, and he was playing on a high ankle sprain. He was getting rid of the ball at the right times and not taking sacks, though he was still taking hits.
Purdy obviously isn’t Mahomes, but it’s not unreasonable to assume that the 49ers offense would’ve had success throwing the ball against the Eagles defense after seeing the way the Chiefs exposed the Eagles secondary.
And it’s a common tactic to send extra defenders at the quarterback on play action, especially in an era when the Shanahan offense is taking over as the NFL’s predominant offensive scheme.
The tactic is commonly referred to as “green lighting” the quarterback where the defense commits an extra defender to the quarterback on play action. This has the result of rushing the quarterback’s throws and forcing offenses to take the short checkdowns by taking away their ability to hit an explosive pass play over the top.
This appeared to be the Eagles strategy early on versus the 49ers and they were lucky it worked. Fans might want Shanahan to scrap the game plan at that point but doing so early on when your scripted plays tell you everything you’ll need to know for the rest of the game would have been just as detrimental to losing Purdy. They’re relying on certain plays and formations to tell give them insight into how their opponent will align and play certain formations in certain situations.
It was an unfortunate event at a crucial time and it led to a frustrating second road NFC championship game loss in a row. The Super Bowl would’ve been another a tough test for a Purdy-led 49ers team but we’ll never really know.
For now, Purdy’s surgery this past Friday in Texas to repair his right throwing elbow is complete and at some point this year he will be cleared to throw and possibly. His status as QB1 or QB2 for the season is up in the air though because it’s going to depend on what Trey Lance does with all the first team reps and it’s highly likely Lance opens the season as QB1 anyways.