While his teammates flew to Kansas City, Mo., for a much-needed off day, A's pitcher Rich Harden was scheduled to fly home Wednesday night to Oakland to get an MRI on his back after departing in the fourth inning. Harden felt the right side of his back tighten during the last hitter he faced, a walk to Hank Blalock, with one out in the fourth inning. Harden, who struck out six of the first nine batters he faced, didn't deny he was still in pain as he talked to reporters after the game. In September 2003, Harden missed a start due to back spasms. He was on the disabled list twice last year with injuries near the back: his left oblique and right lat (just below the shoulder). "I know everybody is hoping that Harden will be OK," reliever Justin Duchscherer said. "To me, he's our stopper. We need him to get healthy as quickly as possible."