(UNDATED) - One day after announcing he was stepping away from baseball, Yermin Mercedes was back with the Chicago White Sox's Triple-A affiliate Thursday. The White Sox confirmed Thursday that Mercedes, the surprising rookie who carried the team with his booming bat early in the season and then got sent to the minors after a prolonged slump, was in uniform for the Charlotte Knight's 5-3 loss to the Durham Bulls. Mercedes, who did not play Thursday, also apologized in an Instagram post. It was a turnaround from his since-deleted post Wednesday night that included an image with the words "it's over." He wrote in the caption that he was stepping aside from baseball indefinitely. Hall of Fame manager Tony La Russa vowed after Wednesday's loss to Minnesota to reach out to Mercedes and insisted the player has a "big league future." Mercedes, 28, sparked Chicago's offense through the opening months of the season, batting .415 with five homers and 16 RBIs in 22 games in April. In May, Mercedes angered La Russa by homering on a 3-0 pitch in the ninth inning of a game the White Sox led 15-4. Mercedes eventually cooled off, hitting .150 (16-for-107) over his final 31 games with Chicago before being demoted to Charlotte on July 2.