True, but the question is: Is he better than Silva or Gorzellany this year? The sample size is small, but so far, he isn't. Unless you go with a six-man rotation, somebody has to move to the pen.
I usually don't drag up the rantings of other Cubs web forums, but is it totally ridiculous to think about moving Z to closer when Lilly comes back? Z isn't the "ace" we need him to be. Marshall, Marmol and Z could anchor a bullpen fairly well, I think.