The 49ers began preparing for the worst by signing Ziggy Ansah. They were hoping for the best.
Unfortunately for the 49ers and Nick Bosa, the MRI confirmed the defensive end tore the anterior cruciate ligament in his left knee during Sunday’s game. The team announced the bad news Monday evening.
Bosa, 22, will undergo season-ending surgery.
He made nine sacks last season in earning defensive rookie of the year honors and added four more sacks in the postseason.
Complicating matters for the 49ers is Solomon Thomas, the former No. 3 overall choice, injured his leg Sunday and could miss significant time. That leaves pressure on first-round rookie Javon Kinlaw to pick up the slack and Ansah immediately to contribute.