I would hold on to Workman. He's gotten better every at every level (3.71 ERA in A, 3.57 ERA in AA, 2.80 ERA in AAA). Overall this year, he's had a 3.21 ERA, 1.18 WHIP, 2.7 BB/9 and a 9.6 K/9 between AA and AAA and he's made a relatively seamless transition to the major leagues. He could easily pitch better than Peavy this year and he's cheap and cost controlled.