Because Greinke wants to play for a winner. He's also a smart guy and understands the business. If they truly don't want to negotiate in-season, then trading Greinke is the best plan. I know chances are slim to resign him anyway which is why they should try and get something out of him. But they could easily tell him: "Look you know we're probably out of it (if in fact they are something like 10 games under or whatever in July). We want to keep you but we also realize there will be a lot of other teams bidding on you. In order to better our ballclub for the future, we are going to trade you. This in no way reflects any desire that we don't want to keep you. In fact, it's the opposite. We want to improve our ballclub and hopefully prove to you that we can build a winner and maybe we can work out a deal in the offseason. We thought we had a great ballclub this year but unfortunately, injuries and a few slumps derailed the season. With a healthy team next year, plus the addition of some good young pitching prospects coming up, as well as the impact bat we're getting for you, we should have a very good ballclub. If you resigned with us, that would put us over the top and we could make a very good run at the playoffs and possibly World Series." I think Greinke wouldn't hold it against the Brewers by trading him because he understands the situation. He might even appreciate being traded to a potential winner because he wants to win. Sure if he went to Texas and won a World Series, they would really want to resign him. But they also paid a ton for Darvish and Hamilton's a FA as well. The point is, aside from signing Greinke to an extension in-season, which is looking more and more doubtful as the days go by, trading him for an impact bat and then making him an offer in the offseason is the best plan.