Wong, 23, struggled at the end of last season but was given the Cardinals starting job at second base to start the 2014 season. He responded by hitting just .225/.276/.268 with five RBI in his first 20 games this season.
The Cardinals will hope that Wong can figure it out at Triple-A before giving him another shot at the big league level. To take his place the team recalled infielder Greg Garcia.
Garcia, 24, will give the Cardinals a replacement for Wong. He was off to a .277/.362/.554 batting line with five home runs and 14 RBI in 20 games for Triple-A.
Mark Ellis will also see time at second base.