Cobb (groin) was activated from the 10-day injured list ahead of his scheduled start Thursday against the Yankees.
He'll toe the rubber for Baltimore's home opener after missing the Orioles' first six games of the season while recovering from a mild groin strain suffered in spring training. Due to multiple off days in the schedule thus far, the Orioles have been able to get by with a three traditional starters while using Nate Karns as an opener on two occasions, so Cobb's addition won't result in any pitchers moving out of the rotation.