Per Mark Gonzales, Jesse Crain is feeling "slightly" better but still experiences some pain throwing long toss. The righty reliever hasn't pitched since March 12 due to an oblique injury -- the same type of injury that kept John Danks out for a month last year.
Opening Day is two weeks from Friday, and the possibility Crain won't be ready to go on April 6 certainly exists. He probably doesn't need much in the way of preseason preparation, but an inning or two under his belt before Opening Day probably couldn't hurt.
James has a good writeup on the situation over at White Sox Observer, pointing out that Addison Reed and Hector Santiago stand to gain the most if Crain isn't healthy to start the season. The depth of the bullpen would certainly be stretched, as it'd be on Will Ohman, Reed and Santiago to handle the bulk of the seventh and eighth-inning workload.
And early in the season, when starters may not be completely stretched out, the Sox may need to rely on those guys a little more than they would in, say, July. But Crain also shouldn't rush his return and risk aggravating the injury again.
It's a tricky situation, and one to follow for the next few weeks.