The San Francisco 49ers were unable to keep up with the Detroit Lions in their home finale on Monday Night Football in Week 17. They lost 40-34, their 10th loss in an injury-riddled 2024 season and their sixth in the last seven games.

You can potentially add another injury to the list: quarterback Brock Purdy.

Purdy rushed for a career-high 377 yards in the game, but was eliminated late in the fourth quarter after a sack by Lions safety Brian Branch.

After the game, Purdy left the game and was replaced by Joshua Dobbs, who scored a 7-yard touchdown run on the 49ers’ final drive of the game.

San Francisco coach Kyle Shanahan said after the game that Purdy’s status for Week 18 against the Arizona Cardinals was uncertain due to a nerve issue in his elbow.

Purdy will undergo further testing on Tuesday.

At 6:10, the 49ers are no longer in the playoffs this season.

If he were to miss, he would be the last significant injury to the 49ers’ offense. San Francisco played its Week 17 game against the Lions without left tackle Trent Williams and left guard Aaron Banks.

Running back Christian McCaffrey and wide receiver Brandon Aiyuk also missed significant playing time due to injuries.

49ers QB Depth Chart

San Francisco traded to Dobbs after Purdy’s injury. The team also has quarterback Brandon Allen on the active roster. Allen started for Purdy in Week 12 against the Green Bay Packers and suffered a 38-10 loss.

It’s unclear whether Dobbs or Allen would start in Week 18 if Purdy is out.

The 49ers also signed quarterback Tanner Mordecai to the practice squad.

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This article originally appeared on USA TODAY: Brock Purdy injury: 49ers QB could miss Week 18 after MNF injury