Before Friday night's contest against Boston, Rivera told reporters he has been pitching with a right-shoulder issue and results of tests taken in New York Thursday revealed shoulder inflammation and calcification.
He said on the Yankees' Web site that minor surgery is one of two options that could correct the ailment.
The other, a series of continuing cortisone injections, also could alleviate the soreness.
"If I don't get surgery, then I have to deal with what I've been doing for the last two years," Rivera said. "It's a decision that I have to make. I'm the one who is pitching. If the best thing for me is to get the surgery, then I will."
He said surgery would not affect his availability for the 2009 season.
Rivera has compiled 481 saves in 14 major league seasons.