Tiger Woods reportedly found time to let loose before undergoing knee surgery.

MSNBC reported that Woods held a celebration with "a bunch of friends" at The Bank nightclub at The Bellagio in Las Vegas on June 22.

"They were all having fun," an onlooker told MSNBC.

According to reports, the party drank Dom Perignon Rose. According to the L.A. Times, a bottle from the 1996 vintage runs about $455.

Woods underwent surgery Tuesday to repair the anterior cruciate ligament of his left knee. Doctors said the surgery went well and didn't expect there to be any long-term effects.

The procedure marked Woods' second knee surgery in 10 weeks. He previously had surgery to clean out cartilage in his left knee after this year's Masters.

Woods claimed his 14th major crown with a victory over Rocco Mediate after 91 holes at the U.S. Open.

The world's top-ranked golfer announced after winning his third U.S. Open crown that he would have knee surgery to repair his ACL and remain out of competition for the rest of the season.