Doug Fister has elbow inflammation. Had an MRI & will rest few days. Matt Williams isn’t concerned. Fister told him he’d pitch if in season.
— James Wagner (@JamesWagnerWP) March 7, 2014
It doesn’t sound like it’s a huge big deal at the moment — the indication is that Fister would have continued to pitch if it was the regular season — but you’re never comfortable with a pitcher who’s reporting elbow trouble.
Fister missing any chunk of the season with arm troubles would changer the calculus of the trade in hindsight, but hindsight isn’t generally a good way to evaluate trades (because you can only trade based on what you know — or should know — at the time of the deal). There aren’t any indications that the Tigers were concerned about Fister’s physical health going into the offseason (and he didn’t miss a lot of time as a member of the Tigers), so this just looks like a bit of bad luck for Washington.
Either bad luck or nothing, depending on the eventual length and severity of the “injury”. It might just be something that goes away with a little bit of rest.