San Francisco 49ers' Jimmy Garoppolo suffers season-ending torn ACL

The San Francisco 49ers' fears were confirmed Monday, as additional tests showed that starting quarterback Jimmy Garoppolo did in fact tear the anterior cruciate ligament in his left knee during Sunday's loss to the Kansas City Chiefs, the team announced.

Garoppolo, who signed a $137.5 million contract with the 49ers in the offseason, is expected to miss the remainder of the season.

The injury occurred with less than six minutes remaining, as Garoppolo finished a 13-yard run down the sideline. While attempting to elude a Chiefs defender, he planted his left leg and his knee appeared to buckle. The 26-year-old was later carted to the locker room, and coach Kyle Shanahan confirmed after the game that the team feared the quarterback had torn his ACL.

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Garoppolo, a former second-round pick who was acquired in a trade with the New England Patriots last season, had posted a 6-1 record as San Francisco's starter entering Sunday.

Backup C.J. Beathard is the only other quarterback on San Francisco's 53-man roster. Shanahan said San Francisco planned to promote Nick Mullens, a second-year QB, from its practice squad, though veterans Tom Savage, Kellen Clemens and T.J. Yates are all scheduled to work out for the team.

The 49ers also lost starting running back Jerick McKinnon to a torn ACL in the preseason.

Shanahan also said Monday that cornerback Richard Sherman had a calf strain and would miss a couple of weeks.