Player #10 checks too, also afraid of the flush.  Player #6 bets $4.

There is no way I will fold this hand for one bet.  There is now $50 in the pot, and calling would cost me only $4.  If I have even a 12.5% chance to win, I should call.  However, I can't raise, either.  Player #10 would fold to a raise since I'm certain that he doesn't have the flush (there's no way he would have checked on the river with one player left to act).  Plus, if I call, there's a chance that Player #10 will make a crying call for $4, which I still have a chance of winning.

I call $4 and Player #10 folds.
 
Player #6 shows down

I win the $54 pot ($51.50 after the rake) with a straight to the five.

Player #6 has two pair. This hand makes sense now. A-T suited is usually a raising hand (at least, I would raise with it), but Player #6 probably did not want to raise after two people had already called the big blind. I really thought I was beaten by a full house more than the flush, but this hand just proves that you can't fold a made hand on the river for one bet if you have a reasonable chance of winning. Saving $4 would have cost me $47.50.