Clubs may view McCarthy as being similar to another recent Rangers discard: right-hander Rich Harden. With both pitchers, the output can be very good – but the quantity of innings is a major question.
McCarthy was a starting pitcher when last we saw him with the Rangers organization in 2009. He has a history of arm problems, however, including a stress fracture in a shoulder blade and inflammation around the elbow in 2007 and 2008.
In 2010, he never made it above Triple A, where he had a 3.36 ERA, 7.03 strikeouts per nine innings and 1.76 walks. That translates to 18.9 percent of plate appearances ending in a K and 4.7 percent in a walk. His FIP was 4.62. (First Inning stats). He's also apparently beating up on the Venezuelan winter league.
Normally I'd say McCarthy is exactly the kind of player you buy speculatively. Maybe he turns out. Maybe he doesn't. But if Morosi's reports of six other teams chasing him are true, you can probably count on him finding exactly the right fit financially, making the risk higher and the bargain less so. That makes the situation a bit more tricky.
As competition for Armando Galarraga, it seems fine. But we really need to see Detroit finding help closer to the top of the rotation if it wishes to compete fully with the Twins and White Sox next year.