How did Raiders backup QB Jarrett Stidham rock the 49ers’ NFL-best defense?

How did Raiders quarterback Jarrett Stidham set the 49ers’ NFL-best defense on edge in ways nobody expected? Tape tells the story.

When the Las Vegas Raiders took on the San Francisco 49ers on Sunday, it was probably expected that 49ers quarterback Brock Purdy, the rookie Mr. Irrelevant who had led the NFL in passer rating (110.0) since he became the team’s starter in Week 13, would deal with the Raiders’ pass defense, which ranked dead last in DVOA. And that happened. In San Francisco’s 37-34 overtime win, Purdy completed 22 of 35 passes for 284 yards, two touchdowns, one interception, and a passer rating of 95.4. As has been the case throughout his improbable recent journey, Purdy did all he could to win.

What we did NOT expect in this game was for new Raiders starter Jarrett Stidham, the 2019 fourth-round pick of the New England Patriots, thrust into his first NFL start against the NFL’s best defense, to do as much. Stidham had completed 24 of 48 passes for 270 yards, two touchdowns, four interceptions, and a passer rating of 46.4 in two seasons with the Patriots.

Former New England offensive coordinator Josh McDaniels clearly saw something in Stidham, because soon after McDaniels became the Raiders’ head coach, Las Vegas traded a 2023 sixth-round pick to the Patriots for Stidham and a 2023 seventh-round pick. The only action Stidham had seen in the 2022 regular season before Sunday’s game was in Week 8 mop-up duty against the New Orleans Saints in a 24-0 loss. But with McDaniels’ decision to bench Derek Carr — a move that likely presages the end of Carr’s time with the franchise — it was now up to Stidham, who completed eight of 13 passes for 72 yards against the Saints, to create necessary explosive plays against a defense that had been a nightmare for opposing quarterbacks all season long.

This can’t be overstated. McDaniels was throwing Stidham into the teeth of a defense that was ranked first in Defensive DVOA, first in Weighted Defensive DVOA, and fifth in Pass Defense DVOA, The 49ers had allowed just 16 passing touchdowns to 15 interceptions. In today’s NFL, if your defense is about even in those two numbers, your defense is amazing. And the 49ers’ defense has been that way all season long.

So, how did Stidham rock that defense with 23 completions on 34 attempts for 365 yards, three touchdowns, two interceptions, and a passer rating of 108.1, against a defense that had allowed a season-long passer rating of 82.3, third-best in the league behind the Denver Broncos and the New York Jets?

And to get granular about it, how is it that Stidham was responsible for eight explosive passing plays in this game, when he was 0-for-2 against the Saints in throws of 20 or more air yards? Against such throws this season, the 49ers had allowed 16 completions on 38 attempts for 550 yards, three touchdowns, two interceptions, and an opponent passer rating of 93.6 (about middle of the pack). This wasn’t the Raiders taking advantage of a heretofore unknown weakness in DeMeco Ryans’ defense — this was the Raiders dictating to that defense in ways no other team has this season.

Interesting questions, so let’s dive under the hood and see how it came to be.