Starting Cardinals shortstop, Aledmys Diaz, was optioned to the team's triple A affiliate on Wednesday. The struggling Diaz is batting .260 with 7 homeruns and 20 RBI.
In a corresponding move, the Cardinals have purchased the contract of former Arizona baseball player and rookie infielder, Alex Mejia.
Mejia, 26, has split time between Springfield (AA) and Memphis (AAA) this season. Mejia has batted a combined .253 with three home runs and 27 RBI in 74 games between the two clubs this season. He was a fourth-round pick from the 2012 draft.
Mejia, who will be making his Major League debut, has been assigned uniform no. 54.