Bo Schultz will start Sunday against the Padres at Salt River Fields, while Randall Delgado will throw in a Minor League game that day.
• The competition for the starting shortstop job remains tight between Didi Gregorius and Chris Owings.
"Defensively, I think you'd give Didi an edge; offensively, give Owings an edge," Gibson said. "We knew that going in. Didi's probably got a little more range, a little more athletic with his arm. C.O. is probably a little more vanilla fielding, but then again offensively I would say C.O. probably has a little more in there. So they're both very talented young kids with good futures with us."
• Gibson said Bronson Arroyo's back was better Thursday, one day after receiving an epidural shot.
"Bronson's around today," Gibson said. "He feels much better, he's improved, so we still feel there's enough time for him to be ready by the beginning of the season for whenever we might slot him in."
Steve Gilbert is a reporter for MLB.com. Follow him on Twitter @SteveGilbertMLB. This story was not subject to the approval of Major League Baseball or its clubs.