Gary Sheffield and the Yankees got the bad news they feared on Thursday, learning that his left wrist is so injured that he could be disabled for the rest of the season. The Yankees said Sheffield has a torn ligament and a dislocating tendon in his left wrist. They have opted not to have him undergo surgery for now, essentially hoping it will heal itself -- or at least heal enough for Sheffield to play without feeling too restricted while swinging. General manager Brian Cashman, calling it "a serious injury," said Sheffield's wrist will be immobilized in a splint for the near future to see if the swelling subsides. But he would not come close to promising this "conservative treatment" will work. If the doctors determine that Sheffield's wrist is not healing as quickly as hoped, the next option likely will be surgery, which very well could be season-ending. "To be quite honest, I can't rule out surgery," Cashman said.