sentences:  Two days earlier it was reported that Burton did not have to go on the disabled list, but he was bothered by it in a bullpen session the day before he was due back.On August 4, he suffered another setback while throwing in a bullpen session, when he felt tenderness in the muscle.Finally, on August 15, Burton threw a pain free bullpen session and followed that up with another painfree simulated game on August 22.