Washington — Mike Hampton's protracted comeback trail took another turn Wednesday when the pitcher left a minor-league game with more discomfort in his left pectoral muscle.

He left in the fourth inning of Class AAA Richmond's game at Durhman, N.C., after throwing 71 pitches in what had been an encouraging outing to that point.

"We were counting heavily on him," said Braves manager Bobby Cox, who had the left-hander scheduled for a May 10 start at Pittsburgh, but will have to reassess that plan as the Braves' rash of injuries continues unabated.

"He went 31/3 [innings] and felt it, is all I know," Cox said, adding that he wouldn't know more until the Braves see Hampton after they return to Atlanta. "He came out [of the game]. Maybe he came out just in time."

Hampton hasn't pitched in a major league game in 32 months because of sundry injuries and two elbow surgeries. He strained his left pectoral muscle in his pregame warmup before a scheduled April 3 start against Pittsburgh.

Wednesday was his second rehab start, and the plan was to make one more before being activated from the disabled list. That plan will likely change.

With John Smoltz back on the disabled list, the Braves were hoping Hampton might finally get healthy and help take up some slack.

They planned for him to throw 70-75 pitches Wednesday, and the hitter he was facing when he left probably would have been his last anyway. Chuck James was warming up in the bullpen at the time.

Hampton didn't finish the batter. He threw a first-pitch strike, then signaled to the dugout. Moments later, Hampton walked off with the Richmond trainer.

"I'll wait and see when we get home," Cox said. "I had him penciled in for the 10th. I was hoping he'd make that and go six or seven innings."

The Braves will probably keep waiting for Hampton, who's making $15 million in the final season of an eight-year, $121 million contract signed with Colorado