Oklahoma City guard Russell Westbrook had surgery on his right knee Friday and will be out through the All-Star break.
"Russell has been playing pain free, but recently had experienced increased swelling," Thunder General Manager Sam Presti said. "After consultation and consideration by his surgeon in Los Angeles, a plan was established to monitor the swelling that included a series of scheduled MRIs.
"On the most recent MRI it was determined by the surgeon that there was an area of concern that had not previously existed, nor was detectable in the previous procedures, and it was necessary to evaluate Russell further.
"The consulting physician determined that arthroscopic surgery was necessary to address the swelling that was taking place. We know that Russell's work ethic and commitment will help him return to the level of play that we have all come to appreciate."
Westbrook is averaging 21.3 points and seven assists for the Thunder this season.