Initially I would have said that the ESPN Cafe on the Boardwalk would be the place to be. I'd maybe still give it a chance but you would most likely want to get there an hour before the game starts (so between 2-2:30pm est.). Other than that, it really depends on where you are staying and if you will have a car or relying on Disney busses. I would think that most of the resort bars will have the game on with like minded fans watching so it then comes down to which bars have the best atmosphere. If the weather is nice, the pool bars at any of the deluxe resorts are nice, as are the indoor bars at the DVC resorts. And those are more likely to be less crowded on a Sunday afternoon. But again, try ESPN Cafe first because you are definitely going to have the full fan experience there.