The Rays have claimed relief pitcher John Gaub off of waivers from the Cubs (via MLBTR). Gaub, a lefty, spent most of 2011 in triple-A, tossing 55.1 innings with 40 walks and 75 strikeouts. He finished with a 3.42 ERA (4.12 FIP). He also pitched 2.2 innings with the Cubs, giving up 2 runs on 12 hits and 2 walks.
This could explain why Kyle Farnsworth had not been placed on the disabled list yet.
[UPDATE: Farnsworth has been replaced on the roster by Josh Lueke. Gaub would appear to just be for triple-A depth.]