On paper it seems like the wrong decision. However, I think it was the right decision, even though it lowered the win probability. 1. The win probability was only lowered 5% by letting in a run for free, which really isn't that much for the 9th inning, where it can sway dramatically. 2. Win probability is based on history, that's it. It doesn't take into account who is pitching, who is batting, which ballpark they are playing in, which runners are on base, etc. Taking that into cousideration, here's an argument on why Maddon was right: Hamilton isn't exactly known for his speed. He has 7 SB this year, so the odds of him making it all the way home on a Byrd double are fairly slim, especially since I assume the outfield was guarding against that. Thus, only a Byrd HR or triple would tie the game, and maybe a double 25% of the time. Byrd has 8 HR, 2 triples, and 19 doubles--not exactly big slugging numbers. Hamilton has 28 HR. Thus, Hamilton was much more likely to tie the game than Byrd, especially if you consider that Hamilton has hit 17 of his home runs at home. Although it is impossible to accurately measure the actual win probability, I suspect that if this scenario was played out 100 times either way, the Rays would win slightly more often by walking Hamilton.