Zab could hurt Cotto but Cotto has heart as evidenced against Torres and Corley. Zab' s heart and willingness to dig deep are questionble at best. And I don't think he liked PBF's bodyshots, I don't think he'll be able to take Cotto's on a consistent basis. Zab's speed could cause Cotto issues but if Cotto's power will see him through imo.