San Francisco 49ers Pro Bowl defensive end Nick Bosa suffered a torn ACL during Sunday's victory against Arizona and will need season-ending surgery, sources told ESPN's Adam Schefter on Monday.
Testing revealed a clean tear, sources told ESPN.
Bosa left Sunday's 16-15 victory with about a minute left in the first quarter. On the play, Bosa was rushing Cardinals quarterback Kyler Murray from the left side and engaged with left tackle Kelvin Beachum when Cardinals guard Evan Brown came over for the double team and knocked Bosa to the ground.