Tillman, who struck five of the six batters he faced Monday, was fantastic in his short stint, and manager Buck Showalter said the switch enables Tillman to keep the ball in his hand without a long layoff.
Wright will be making his season debut on Saturday, while Showalter will hold off on announcing a fifth starter for Sunday. With rain in Thursday's forecast, he wants to be sure the O's get that game in before planning for Sunday.
Brittany Ghiroli is a reporter for MLB.com. Read her blog, Britt's Bird Watch, follow her on Facebook and Twitter @britt_ghiroli, and listen to her podcast. This story was not subject to the approval of Major League Baseball or its clubs.