UPDATE (3:20 p.m. ET): It’s official. Jimmy Garoppolo’s season is over.

ORIGINAL STORY: The San Francisco 49ers worst fears reportedly were confirmed Monday.

An MRI revealed Niners quarterback Jimmy Garoppolo suffered a torn ACL Sunday and will miss the rest of the 2018 season, ESPN’s Adam Schefter reported Monday, citing a source.

Garoppolo injured his left knee while trying to pick up extra yardage late in San Francisco’s loss to the Kansas City Chiefs. His loss is a crushing blow for the Niners, who just signed the 26-year-old to the richest contract in NFL history this offseason and now must turn to backup quarterback C.J. Beathard to salvage their season.

San Francisco, which sits at 1-2 after Week 3, is 6-2 with Garoppolo under center since he came over from the New England Patriots last October — and 1-10 without him.

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