Most important to the D-backs' decision-makers was that Delgado, who battled for the No. 5 spot in the rotation this spring, did not allow a walk.
With right-hander Ian Kennedy serving a 10-game suspension, the D-backs are using a four-man rotation. The team can do that because it had Thursday off and has another off-day Monday.
Kennedy is eligible to return next Saturday, so the D-backs will need Delgado or another pitcher to start next Friday against the Braves in Atlanta.
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.