For the third time in four seasons, and for a second straight year, Philadelphia Eagles tailback Correll Buckhalter has undergone season-ending knee surgery. The fifth-year veteran, whose career could be ended by his latest injury, underwent surgery Tuesday to repair a torn right patella tendon. He had surgery on the same tendon last year after sustaining an injury in preseason. Early in camp, he re-injured the knee, and an examination Monday by noted Birmingham, Ala.-based orthopedic surgeon Dr. James Andrews revealed the new tear. Team officials last week conceded to ESPN.com that they were concerned about the latest injury and broadly hinted it could be season-ending. Andrews had recommended earlier that Buckhlalter receive treatment and rehabilitation on the knee for a week and then have it re-examined. When the Eagles did not offer an update on Buckhalter's status Tuesday, after his visit with Andrews a day earlier, it was viewed as an ominous sign. An announcement of the surgery then came on Wednesday morning.