Mike Hampton's return to the mound is once again in a holding pattern. Or a disabled pattern.

The Braves pitcher landed on the 15-day disabled list once again, this time for a strained pectoral muscle in the left side of his chest, which flared during his pregame warmup Thursday night.

The left-hander was scratched minutes before his scheduled start against Pittsburgh, which was to have been his first regular-season game in 31 1/2 months.

"It's unbelievable that something else could pop up like that," said manager Bobby Cox, who announced that left-hander Jo-Jo Reyes would be brought up temporarily from Class AAA Richmond and that lefty Chuck James would join the rotation in Hampton's place before his next scheduled turn.

James (shoulder) will be activated from the DL on Sunday. He was scheduled to begin the season in the Richmond rotation, but that plan changed abruptly with Hampton's latest injury.

"Nobody's more disappointed than I am," said Hampton, who missed the past two seasons recovering from two left-elbow surgeries 16 months apart. "I worked pretty hard to get to this point.

"I hate it for Bobby and the team, and I hate it for myself. ... I don't know if snake-bitten is the word for it."

Hampton said he and Braves doctors believe the injury is minor. He added, "I hope that's all it is."

Cox and the pitcher said Hampton felt some discomfort in his chest when he threw a bullpen session Monday, but that it was better when he threw Wednesday in the outfield.

About 20 pitches into his warmup session Thursday, Hampton said the muscle began to "grab" and he decided he shouldn't risk more serious injury by making the start.

He said it was hard to step off the bullpen mound and tell pitching coach Roger McDowell that he wouldn't be able to start.

The Braves had to scramble and got Jeff Bennett warmed. The start of the game was delayed seven minutes for Bennett, and the right-hander pitched four innings and allowed four hits and two runs.

Hampton missed one start in spring training because of a slight groin strain, but was otherwise healthy and effective, going 1-0 with a 2.16 ERA in 16 2/3 innings over five exhibition starts.

But the fact that didn't make it out of the bullpen was another reminder of the fragile health of Hampton, 35, who has had eight DL stints since 2005.

Left pectoral is added to a Hampton injury inventory that includes right calf, left forearm, herniated disk, left elbow, right hamstring, left oblique, left groin and right groin.

He is making $15 million to finish an eight-year, $121 million contract he signed with Colorado, a record deal at that time.

He's 32-20 with a 3.96 ERA in 72 starts since being traded to Atlanta in November 2002, and last pitched in a real game Aug. 19, 2005.

Hampton had "Tommy John" ligament-transplant surgery Sept. 26, 2005, and surgery to repair a torn flexor tendon April 10, 2007.