Greinke should provide Diamondbacks value even at this price tag

Zack Greinke was, in my opinion, the best free-agent starter on the market this winter, so it's fitting he signed the winter's biggest contract so far and the biggest annual salary in baseball history (so far, at least) for any player. Despite its sheer size and the risk any team faces in signing a free-agent pitcher, the deal has a pretty good chance to work out for the Diamondbacks on paper -- but they're going to have to add a couple of additional pieces to turn this team into a playoff contender.