Yankees pitcher Randy Johnson had surgery Thursday to repair a herniated disk in his back. Dr. Michael Watkins operated on the Big Unit in Los Angeles. Watkins also operated on Johnson's back 10 years ago. "The surgery went fine. The doctor said he was thrilled," said Johnson's agent, Barry Meister. "Randy will return home to Phoenix tomorrow." Yankees general manager Brian Cashman had not spoken with team physician Dr. Stuart Hershon following the operation, spokesman Ben Tuliebitz said. Cashman has said he expects Johnson to be behind the other pitchers when spring training starts in mid-February.