CHICAGO -- - The Chicago White Sox reinstated reliever Aaron Bummer from the 10-day injured list and recalled right-hander Reynaldo López from Triple-A Charlotte on Friday.
The AL Central leaders also optioned relievers Matt Foster and Jace Fry to their top farm club.
Bummer, 27, had been sidelined by a strained right hamstring. The left-hander is 1-4 with a 3.26 ERA and two saves in 32 games heading into Friday night's series opener against Houston.
López has been working as a starting pitcher, but he likely will work out of the bullpen with Chicago.