While we were all beginning the think the White Sox were done with making moves, Rick Hahn has had other ideas.
Guerra was designated for assignment by the Dodgers earlier this month. He was the Dodgers primary closer in 2011 when he had 21 saves. He lost the closer job in 2012 to Kenley Jansen and spent some time in AAA. He also spent some time on the DL and had shoulder surgery during the 2013 offseason. Additional injuries delayed the start of his 2013 season. He spent most of the season at AAA again and pitched in nine games in May for the Dodgers with a 6.75 ERA.
Guerra is a reliever that breaks the mold of this offseason's bullpen additions. He relies mainly on a 93-95 MPH fourseam fastball and a cutter. He also mixes in a curve with a slider against righties and a change against lefties. He did start a few games for Albuquerque last year, but would likely be in the bullpen for the Sox.
This acquisition makes the Sox bullpen situation more complicated, but seems to clarify everything as well. Guerra joins Donnie Veal and Maikel Cleto in the out of options club. If we are assuming Jones, Lindstrom, Bellisario, and Downs are locks for jobs and Veal is a "very likely", the option situation makes Cleto and Guerra the favorites for the last two bullpen spots. Adding in the fact that adding Guerra takes the 40-man roster back to 40, it looks like Zach Putnam, Daniel Webb, and David Purcey seem destined for trips to Charlotte to start the season.