Septimo, a converted outfielder from the Arizona Diamondbacks organization, signed with the White Sox as a minor league free agent in the 2011 offseason. He has since gone on to post two impressive seasons in relief, striking out almost a third of the batters he has faced, while walking only 13 percent.
The 34-year-old Ohman, on the other hand, struggled through his 26 and 2/3 innings in 2012. Though he has played a LOOGY role in the past -- and held left-handed batters to a .186/.250/.305 slash in 2012 -- the White Sox called on him to face 48 righties in the 2012 season, and his performance suffered.
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