Watkins will be optioned to Triple-A Norfolk on Wednesday, Nathan Ruiz of The Baltimore Sun reports.
Watkins has largely been effective as a starter for the Orioles in the second half, but he'll lose his spot in the rotation after giving up nine runs in 10.2 innings over his last two outings. Tyler Wells (oblique) will be reinstated from the 15-day injured list to start Wednesday's game against Toronto, so Watkins will head to the minors to make room on the Orioles' active roster.