The 27-year-old Hanson was once one of the game's top pitching prospects and one of the most promising young starters in the National League after posting a 3.29 ERA in his first 460 1/3 innings at the Major League level. However, a series of shoulder injuries and a concussion have slowed Hanson's career as well as his fastball. After averaging 92.5 mph on his fastball in his first two seasons in the Majors, Hanson has averaged 89.7 mph over the past two seasons.
The Braves traded him to the Angels in exchange for setup man Jordan Walden last offseason, but he found himself non-tendered after a season in which he registered a 5.42 ERA with 6.9 K/9 and 3.7 BB/9 in 73 innings of work. Hanson signed a split contract with the Rangers earlier this offseason but failed to make the club after yielding 10 runs in 14 Spring Training innings. He'll serve as depth for a White Sox team that currently has a rotation which is fronted by Chris Sale and also contains Jose Quintana, Felipe Paulino, John Danks and Erik Johnson.