Mariano Rivera had right knee surgery in New York Tuesday at the Hospital for Special Surgery and said the operation "went as planned.''

Taking to Twitter, Rivera wrote, "My surgery was a success, it went perfectly. I am looking forward to beginning my rehab soon. Thanks as always for your prayers.''

Manager Joe Girardi said he had no idea when the 42-year-old reliever would return.

"I haven't been told how long it will take,'' Girardi said. "We expect him next year.''

According to a statement put out by the club, no work was done on the meniscus. When Rivera was injured the initial test found meniscus damage.