Nick Bosa came into Sunday's 49ers-Panthers game as the NFL's sack leader, but came out of the contest at Bank of America Stadium before it was even over.
The 49ers announced Bosa has been ruled out for the remainder of the game with a groin injury after exiting in the third quarter.
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The loss marks yet another key San Francisco player to sustain an injury this season, though it's not yet clear how severe Bosa's is. Earlier in the game, safety Jimmie Ward was ruled out after sustaining a hand injury in the game's first half -- his first contest back from a previous hamstring injury.
And in the fourth quarter, kicker Robbie Gould was ruled out with a knee injury.
There are currently eight 49ers on injured reserve, including running back Elijah Mitchell, quarterback Trey Lance, linebacker Azeez Al-Shaair and defensive end Jordan Willis.
Bosa's brother, Los Angeles Chargers linebacker Joey Bosa, is expected to miss eight to 10 weeks with a groin injury of his own.
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Prior to Sunday's Week 5 clash, Bosa was at the top of Defensive Player of the Year conversations to start the young 2022 NFL season.
The 49ers held a 24-12 lead over the Panthers following Bosa's exit.