Wolf would have been on regular rest after Wednesday's 3-1 victory over the Athletics. Wolf, called up from Round Rock because Nick Tepesch had to be scratched with of a blister, allowed one run on three hits and two walks over five-plus innings while striking out three. It was his first start in the Major Leagues and his first appearance there since 2010. But the Rangers decided on Perez.
"Whatever they want me to do. ... If I don't start, I won't be disappointed," Wolf said before Friday's game. "Like I said many times before, I never thought I would make it back up here."
Wolf could move to the bullpen, at least for the twin bill. The Rangers are allowed to carry 26 players for the doubleheader but would have to make a roster move after it is over to get down to 25.
T.R. Sullivan is a reporter for MLB.com. Read his blog, Postcards from Elysian Fields, and follow him on Twitter @Sullivan_Ranger. This story was not subject to the approval of Major League Baseball or its clubs.