The Orioles four minor league full-season affiliates begin play tomorrow night. Chris Tillman is the scheduled starter Thursday at 7:15 when the Tides open at home vs. defending International League champion Durham. Those expected to join Tillman in the Norfolk rotation are Jake Arrieta, Brandon Erbe, Troy Patton and Alfredo Simon. We have not heard the rotation order after Tillman. Zach Britton, the Carolina League Pitcher of the Year in 2009 at Frederick, will make his Double-A debut and get the start in the opener for Bowie, when the Baysox host Richmond Thursday night at Prince Georges Stadium. He will be joined in the Baysox rotation by Steve Johnson, Chorye Spoone, Ryohei Tanaka and Tim Bascom. Lefty Rick Zagone is expected to be Frederick's starter Thursday when the Keys open at Lynchburg. He will be followed in the rotation by Ryan O'Shea, Nate Nery, Cole McCurry and Oliver Drake. Drake will start the Keys opener next Tuesday vs. Myrtle Beach. The Delmarva Shorebirds open at Greenville Thursday night after an exhibition victory over Salisbury State. The Birds home opener is set for April 16th. Delmarva has not announced its opening pitcher but the Shorebird rotation is expected to include Ryan Berry and Matt Hobgood.