The Cardinals recalled Leahy from Triple-A Memphis on Sunday.
The move corresponds with the Cardinals designating right-hander Giovanny Gallegos for assignment. Leahy's last major-league outing was July 21 against Atlanta, when he pitched two scoreless innings and notched his first major-league save. Across 19 major-league outings this season, Leahy has a 3.90 ERA and 1.05 WHIP across 32.1 innings.