Schoop suffered the injury last night during a swinging strikeout, and was removed from the game in the seventh inning.
He received good news Saturday, when it was revealed his oblique strain was mild, but it would still be an outlier if he only missed 10 days with the injury.
Cobb, one of the top starters available in free agency this past offseason, didn't finalize his four-year, $57-million deal with Baltimore until the penultimate week of spring training, and consequently wasn't able to break camp with the club.
The Orioles announced the move before Saturday's game against the Red Sox and activated pitcher Alex Cobb in a corresponding move. "It's honestly the most comfortable I've felt being in this locker room, somewhere I'm familiar with, in the clubhouse around guys that I know".
Schoop was off to a slow start in 2018 with a.230/.266/.344 slash line and one home run in 14 games. Schoop's right oblique strain is the Grade 1 (least severe) variety, so the Orioles are optimistic his absence will be a short one. Over parts of six seasons in the majors, all of them coming with Tampa Bay, Cobb owns a 3.50 ERA (111 ERA+) across 115 starts.