Mayers' contract was purchased by the Cardinals on Sunday. He'll make his major league debut against the Dodgers.
Mayers will take the place of Miguel Socolovich (optioned to Triple-A Memphis) on the Cardinals' 25-man roster, earning his first turn in a major league rotation after posting a 2.94 ERA over nine starts with Triple-A Memphis this season, notching 43 strikeouts, but has struggled with command (19 walks). The move was made following the team's doubleheader Wednesday to allow Carlos Martinez regular rest for his next start, so this will likely be a single start before Mayers returns to the minors.