Oakland Athletics' third baseman Eric Chavez had his third operation in two months, a procedure Friday to remove damaged tissue from his left shoulder. He is expected to begin physical therapy in about a week. The six-time Gold Glove winner had right shoulder surgery Sept. 5 for a torn labrum and to repair a damaged biceps tendon and remove a loose body from the joint. Dr. Lewis Yocum performed that operation. Chavez had surgery on his back Oct. 9.