Athletics manager Mark Kotsay confirmed that Morris will start Saturday's game in Houston, Chris Correa of the Turlock Journal reports.
The Athletics called up Morris from Triple-A Las Vegas on Tuesday, and after he wasn't needed in relief in any of the ensuing four games, he'll make his MLB debut Saturday as the club's new fifth starter. Prior to receiving his promotion, Morris compiled a 4.45 ERA, 1.47 WHIP and 49:26 K:BB over 60.2 innings with Las Vegas in the hitter-friendly Pacific Coast League. Since neither Luis Severino (shoulder) nor Aaron Civale (shoulder) appear especially close to returning from the injured list, Morris has a path to making multiple turns through the big-league rotation. If Morris performs poorly in Saturday's contest, however, the Athletics could swap him out of the rotation for Mason Barnett, who is stretched out enough to handle a starting role after tossing four shutout innings in long relief during Friday's 5-1 loss to the Astros.