Of the operation, Oakland manager Bob Melvin called it "very successful."
Sizemore is resting comfortably in Florida, according to the club, and will return to the Bay Area on Saturday to begin rehab. As expected, he will miss the rest of the season, after sitting out all of 2012 with the same injury.
The 28-year-old infielder was playing in just his second game of the season last week in Anaheim when he suffered the ACL tear.
Jane Lee is a reporter for MLB.com. Read her blog, Major Lee-ague, and follow her on Twitter @JaneMLB. This story was not subject to the approval of Major League Baseball or its clubs.