The surgery was performed Friday by orthopedic surgeon James Andrews in Pensacola, Fla. The team says Gay should be ready for the start of next season.
Gay was hurt Feb. 15 against Philadelphia. He underwent weeks of rehabilitation but the team said Tuesday that he will miss the rest of the season.
The 6-foot-8 Gay averaged 19.8 points per game and 6.2 rebounds per game this season. The Grizzlies are 9-6 in his absence as they try to make the Western Conference playoffs for the first time since the 2005-2006 season.