It is a tight race. When Milton went down, Elizardo came up, but I honestly think he shouldn't even be in consideration for going down. He is young, and is pitching very well at the moment.
That leaves Williams and Claussen. I say Claussen goes. To me, Willimas has better 'stuff' because of his curve. However does Claussen have any options left? It could be Williams just because he has an option.