The Cardinals selected Roycroft's contract from Triple-A Memphis on Monday.
Signed out of the independent ranks in June 2022, Roycroft had a rapid climb through the Cardinals' farm system while excelling as a middle reliever/setup man across his three stops in the minors. Before getting his first big-league call-up Monday, the 26-year-old right-hander had pitched exclusively for Memphis this season, logging a 1.38 ERA, 1.23 WHIP and 9:6 K:BB in 13 innings. He'll likely work in lower-leverage spots out of the St. Louis bullpen initially.