Right-hander Brandon Backe was activated from the disabled list by the Astros, who also purchased the contracts of right-handed pitchers Brandon Duckworth and Scott Strickland from Triple-A Round Rock and designated infielder Todd Self for assignment. Backe, likely to return to the rotation Wednesday at Philadelphia, had been on the disabled list since July 25 with a strained left ribcage. He was 8-7 with a 4.93 ERA in 21 games (20 starts) before getting hurt. In two rehab starts at Double-A Corpus Christi, Backe allowed just two earned runs over eight innings with 11 strikeouts.