The Braves got better because they didn't even have a replacement level CF on the roster. BJ is an easy 3 wins above replacement and probably a net of 4 wins for the Braves.
Hanson's been falling apart in recent years. This trade signals that the Braves do not expect him to recover. He very well may, but I'm going to trust that the Braves know how to evaluate their pitchers.
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