(Photo credit: Cary Edmondson-Imagn Images)San Francisco 49ers star defensive end Nick Bosa's season is over due to a torn ACL, head coach Kyle Shanahan confirmed Monday. Bosa underwent testing after hurting his right knee during Sunday's victory over the Arizona Cardinals. The five-time Pro Bowl selection was injured in the first quarter while being double-teamed during an Arizona pass play. He has two sacks and 17 tackles in three games this season for the 49ers (3-0). In 85 games (83 starts), he has 64.5 sacks, 91 tackles for loss, 168 quarterback hits, 278 tackles, 13 forced fumbles and two interceptions.