With one plant of Jimmy Garoppolo’s left foot, the San Francisco 49ers‘ franchise suffered what appears to be the biggest blow possible.

Late in Sunday’s game against the Kansas City Chiefs, Garoppolo was running, planted to cut back and went down with a left knee injury. He came out of the game.

After the game, 49ers coach Kyle Shanahan told reporters in his postgame news conference that the team fears Garoppolo tore his ACL, according to Yahoo Sports’ Terez Paylor. That would knock him out for the rest of the season.

Garoppolo was running upfield on third-and-goal. Because the 49ers trailed late, he tried to stay in bounds and get as many yards as he could. When Garoppolo planted his left foot to cut back upfield, it buckled. He was then hit and tackled down and immediately reached for his knee.

The 49ers trainers came out and started testing his knee. Garoppolo went to the medical tent, and then was carted back to the locker room. If the injury is the worst-case scenario, it’s a horrible blow for a 49ers team that had high hopes coming into the season.

Garoppolo joined the 49ers in a midseason trade last year, and he led a five-game winning streak to finish the season. He signed a five-year $137 million deal in the offseason and was one of the NFL’s bright young stars.

If Garoppolo’s injury is serious, C.J. Beathard will likely take over as the 49ers’ quarterback.

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Frank Schwab is a writer for Yahoo Sports. Have a tip? Email him at shutdown.corner@yahoo.com or follow him on Twitter!
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