The Cardinals optioned Rincon to Triple-A Memphis on Sunday.
He'll give up his spot on the 28-man active roster to left-hander Cooper Hjerpe, who is expected to pitch behind starter Kyle Leahy in Sunday's game against the Rockies. After getting his first big-league call-up Sept. 1, Rincon appeared in two games out of the St. Louis bullpen and surrendered seven earned runs on five hits and one walk over 1.1 innings.