The Astros optioned Alexander to Triple-A Sugar Land on Wednesday.
Alexander was recalled from Triple-A on Tuesday, but he'll head back down after giving up five earned runs over 4.1 innings during Wednesday's loss to the Dodgers. The 33-year-old righty owns a 4.97 ERA and 1.52 WHIP through 29 innings (six starts) in the minors this season and could be called upon to make more appearances in the majors this year, especially considering the number of injuries that have already hit Houston's pitching staff.