The 49ers' worst fears were confirmed Monday.
Last season's NFL Defensive Rookie of the Year, Nick Bosa, will miss the remainder of the 2020 season after an MRI confirmed he suffered a torn left ACL on Sunday.
Bosa sustained the injury during the first quarter of the 49ers' 31-13 win over the New York Jets at MetLife Stadium in East Rutherford, N.J., and was taken by cart to the locker room.
After the game, the 49ers coach told reporters that Bosa "most likely" tore his ACL. Now the team knows for sure.
It's a tough blow for Bosa, who was expected to blossom into one of the best defensive players in the NFL this season. In just his second season, Bosa already had become the most feared player on the 49ers' defensive line.
Bosa wasn't the only member of the defensive line to go down Sunday. Former No. 3 overall draft pick Solomon Thomas suffered a leg injury and could miss significant time. Quarterback Jimmy Garoppolo and running back Raheem Mostert also sustained leg injuries that could keep them out of upcoming games.
The 49ers believe the turf at MetLife Stadium played a big part in the injuries, and the NFL's field operations department reportedly is looking into the situation. The 49ers are scheduled to play at MetLife again next Sunday when they take on the New York Giants.
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Without Bosa and Thomas, the 49ers will need to rely on 2020 first-round pick Javon Kinlaw and other depth options on the roster.
The 49ers picked up their first win of the 2020 season Sunday, but it was an extremely costly victory.