The 49ers might be without Raheem Mostert for a little while.
The team believes the running back suffered a "mild sprain of the MCL," ESPN's Adam Schefter reported Sunday, a few hours after the 49ers beat the New York Jets 31-13 at MetLife Stadium in East Rutherford, NJ.
Schefter reported that Mostert will undergo an MRI to determine the severity of his injury and how much time he will miss.
Mostert began Sunday's game with a bang, taking the first play from scrimmage 80 yards for a touchdown. He carried the ball eight times for 92 total yards, but he was ruled out of the game at halftime.
Despite the injury, Mostert appeared to be in good spirits after the win, based on this tweet he sent out at 2:34 p.m. PT.
The 49ers suffered an unbelievable amount of injuries in the game Sunday. In addition to Mostert, quarterback Jimmy Garoppolo, edge rusher Nick Bosa and defense lineman Solomon Thomas were among those to exit with potentially serious injuries.
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If Mostert is forced to miss an extended period of time, the 49ers can rely on veterans Tevin Coleman and Jerick McKinnon, as well as Jeff Wilson Jr.
Coleman received the bulk of the work Sunday, with 14 carries, but he finished with just 12 yards, although he added two catches for 28 yards. McKinnon gained 77 yards on just three carries -- including a 55-yard run to convert an improbable third-and-31 -- and also scored a touchdown.