Ruiz was a catcher in the early parts of his career, though the Padres transitioned the strong-armed backstop to the mound in 2016. He was added to the 25-man roster as an emergency call-up in 2017, pitching a scoreless inning in his lone big league appearance. The Padres DFA’d him to make room on the 40-man roster for free agent acquisition Freddy Galvis (SS, Padres) this offseason, and the White Sox pounced on Ruiz when he was available on the wire.
He’s a burly 6’1’’ and 190 pounds. I only saw him for a quick inning, but a loud two-pitch mix were notable. He throws a heavy fastball 93-to-96 mph (T97). A true slider in the 83-to-85 mph range tunneled well off his fastball and darted away from hitters with long, sharp, lateral tilt. There was plenty of effort to his delivery and his control and pitchability are far from sure things. Ruiz is still a work in progress as a pitcher, but their have been many successful conversions from catcher to reliever (see: Jason Motte, RHP, Cardinals) for players with Ruiz’s frame and stuff.