Stewart spent 2013, his age-26 season, with Chicago's Triple-A affiliate, posting a 4.25 ERA with 6.6 K/9 and 2.0 BB/9 in 167 1/3 innings of work. Originally a third-round pick by the Reds in 2008, the Texas Tech product has found himself included in trades for a number of high-profile players over the past six years. The Reds dealt him to Toronto along with Edwin Encarnacion and Josh Roenicke in 2008 to acquire Scott Rolen. He was then part of the three-team deal that sent Edwin Jackson to the Cardinals in 2011, and he was acquired by the White Sox to the Red Sox in June 2012's Kevin Youkilis deal. Chicago picked him back up on waivers last offseason.
Stewart has 103 Major League innings under his belt, but he's posted a 6.82 ERA in that time. He's whiffed just 5.6 hitters per nine innings, but has also averaged just 1.9 walks per nine to go along with a strong 50 percent ground-ball rate in the bigs. Both xFIP and SIERA feel his ERA to date should be just a shade under 4.00 rather than at its current level.
Atlanta's acquisition of Stewart isn't entirely surprising; the team looks to be adding depth with Kris Medlen's health status up in the air (he'll undergo an MRI on his right forearm today) along with the possibility that Mike Minor could miss a start or two in April. Of course, Atlanta has in-house options such as Alex Wood, Freddy Garcia and David Hale that would presumably be in line for big league starts before Stewart, who is most likely ticketed for Triple-A. Stewart was not on Chicago's 40-man roster.