ATLANTA -- New York Yankees closer Mariano Rivera underwent surgery Tuesday morning to repair a torn ACL in his right knee.

A Yankees spokesman said the operation "went as planned.'' The club offered no timetable for Rivera's recovery, but the 42-year-old right-hander has said he plans to pitch for the Yankees next season.

"I think we're all expecting to see Mo pitch next year," Yankees manager Joe Girardi said before Tuesday's game against the Atlanta Braves. "I really don't think we're going to see anything this year."

Rivera, who suffered the injury while shagging fly balls during batting practice on May 3 in Kansas City, was operated on by Dr. David Altchek, the New York Mets' team doctor, at the Hospital for Special Surgery in Manhattan.

According to a statement released by the Yankees, Rivera had "an isolated repair on his torn ACL." Nothing was done to repair a torn menisicus in the same knee that Rivera also suffered in the incident at Kauffman Stadium.