The Cardinals claimed Peralta off waivers from the Rockies on Monday.
The younger brother of Freddy Peralta, Luis has spent all of this season at Triple-A Albuquerque, where he's been bludgeoned for 14 runs with a 14:13 K:BB over 7.1 frames. The left-hander has collected a 6.03 ERA and 30:23 K:BB in 31.1 innings during his chances at the big-league level. Peralta boasts a 30.2 percent strikeout rate in the minors but also a 13.9 percent walk rate. He will report to Triple-A Memphis.