Cahill, meanwhile, made his second rehab start Tuesday for Triple-A Reno and allowed four runs (three earned) in 5 1/3 innings. Cahill walked three and threw two wild pitches, and it appeared he might need another Minor League start before rejoining the rotation.
"His start yesterday I thought was decent," Arizona GM Kevin Towers said. "I think he thought it was average. I think when we bring him back here we want to make sure he's in the right state of mind, feels comfortable, he's healthy and feels confident, so probably at least one more rehab start, maybe two."
With that in mind, the D-backs plan on recalling right-hander Zeke Spruill from Reno to start Thursday's game against the Rangers. That would mean that Randall Delgado would be pushed back to Friday, with Patrick Corbin going Saturday and McCarthy on Sunday.
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.