Guerrero has a 5.77 ERA over 113 career games, 112 of those during the past two seasons with the Marlins. He had a 6.26 ERA over 52 games in 2019, but he also has 111 strikeouts in 106 career innings to complement 67 walks and 109 hits allowed.
According to Statcast, Guerrero had 178 pitches thrown 100 mph or above in 2019, the second-most in Major League Baseball behind Jordan Hicks (206). Guerrero's 98.9 mph average fastball velocity ranked as the third highest (minimum 200 fastballs).
Guerrero allowed a .297 average in at-bats ending on his pitches that registered 100 mph and above and a .234 average on his stuff thrown 99 mph or below. He allowed a .405 slugging percentage on pitches 99 mph and below and .486 on the 100 mph and above, with a 70 percent strike rate on pitches 100 mph and above.
At 6-foot-8 and 210 pounds, Guerrero was traded to the Marlins from the Padres on July 29, 2016, with Andrew Cashner and Colin Rea in exchange for Carter Capps, Jarred Cosart, Luis Castillo and Josh Naylor. He was a Futures Game selection in '14 with Class A Lake Elsinore and '17 with Double-A Jacksonville. The native of Bocachica, Colombia, pitched for Colombia in the 2017 World Baseball Classic.
With the move, the White Sox 40-man roster moves to 37.