Jarod Burton spent three years in the Minnesota bullpen with steadily worsening ERAs: 2.18 in 2012, 3.82 in 2013, 4.36 last year. The Twins declined his option early in the offseason, and it took him until the week before camps open to land even a non-roster deal (with the Yankees).
I don't know how likely Burton is to land a roster spot with the Yankees, but I find it noteworthy that the guy elevated to the closers role when Glen Perkins was shut down last September didn't find a market.
I had expected Burton's departure to be just the start of a larger bullpen shakeup this winter, and the Twins did also jettison Anthony Swarzak (who also wound up with a non-roster deal). But Brian Duensing and Casey Fien return as the presumptive setup men to Perkins. and the free-agent signing of Tim Stauffer does not suggest that the Twins intend to push some of their young live arms into the bullpen.
Which is too bad. Duensing and Fien are not high-end arms. Fien was, according to the Bill James Handbook, the non-Perkins reliever used in the highest-leverage situations last year, and he wouldn't be one of Kansas City's top four right-handed relievers. If Fien and Duensing are the guys Paul Molitor relies on in the seventh and eighth innings, the bullpen will not be a true strength,