The D-backs will have to make a corresponding roster move prior to Tuesday's game to make room for Skaggs. Right-hander Randall Delgado was called up from Reno when McCarthy was placed on the DL and has been available in the bullpen the past few days.
Skaggs battled for the No. 5 spot in the rotation during Spring Training, and after struggling at the start of the regular season in Reno, he has pitched well of late. Last Monday, he was added to the roster to start the first game of a doubleheader against the Rangers.
Skaggs was impressive in that game, as he allowed just three hits over six shutout innings, and D-backs manager Kirk Gibson was asked if that will give Skaggs confidence heading into Tuesday's start.
"It should," Gibson said. "He threw all of his pitches. That's what he has to do, and hopefully he'll do that again."
Skaggs had been scheduled to start for Reno on Saturday, but he was scratched from that start so that he would be available to pitch Tuesday.
Steve Gilbert is a reporter for MLB.com. Read his blog, Inside the D-backs, and follow him on Twitter @SteveGilbertMLB. This story was not subject to the approval of Major League Baseball or its clubs.