Flaherty, 20, hurled seven scoreless innings Sunday for High-A Palm Beach. He scattered five hits, did not walk a batter and fanned four.
Flaherty is among the better pitching prospects for the Cardinals, particularly now that Alex Reyes and Luke Weaver have ascended to the big leagues. Flaherty has a 3.83 ERA and 104:39 K:BB in 115 innings. He does not have the upside of Reyes or Weaver, but does have a ceiling of a No. 2 starter.