Chicago ? Cubs right-hander Mark Prior went back on the 15-day disabled list Friday, this time with a strained left oblique muscle.

He got hurt while taking batting practice last Saturday in Milwaukee. Prior, who began the season on the disabled list because of a sore shoulder, came off it June 18 and went 0-4 in four starts with a 7.71 earned-run. He was scratched from his start last Sunday.

Prior is scheduled to throw in the bullpen today and then again Tuesday. He was put on the DL retroactive to July 5, so he could come off next week.