Carpenter begins rehab, Cardinals option Butler

Chris Carpenter started his rehab assignment Monday and the St. Louis Cardinals optioned right-handed reliever Keith Butler to Triple-A Memphis.

Carpenter started for Double-A Springfield and suffered the defeat in a 5-3 loss to Arkansas. He gave up three runs (two earned) on six hits and two walks in 2 2/3 innings. He struck out five.

Carpenter has been on the disabled list all season due to a nerve problem affecting his right shoulder.

He is expected to make three or four starts in the minors before the team brings him back.

Butler had a 1.98 ERA in 12 games with the Cardinals. He is expected to get more consistent playing time in the Memphis bullpen.