Coach Kyle Shanahan told reporters following Sunday's loss to the Kansas City Chiefs that the team feared Garoppolo had torn his ACL. C.J. Beathard, a 2017 third-round pick who went 1-4 as a starter last season, will be the team's starter moving forward.
Garoppolo was carted to the locker room after his left knee buckled on a third-and-20 scramble with the 49ers down 14 late in the fourth quarter. He could have stepped out of bounds but instead cut upfield, planting his left leg just before taking a big hit from Chiefs cornerback Steven Nelson.
Garoppolo was 20 of 30 for 251 yards and two touchdowns against the Chiefs when he went down. He also rushed three times for 23 yards. He finishes the 2018 season 53 of 89 for 718 yards, five touchdowns, and three picks.
The 49ers made Garoppolo the highest-paid player in the NFL, at the time, when they signed him to a five-year, $137.5 million deal during the offseason. The contract included $74.1 million guaranteed.
In 26 career games (10 starts) with the 49ers and New England Patriots, Garoppolo has thrown for 2,968 yards, 17 touchdowns, and eight interceptions. This is the second time he'll miss games due to injury -- he sprained the AC joint in his shoulder in his second career start in 2016 and missed two games.