[mjm]

[ QUOTE ]
I may be way off but I think the way you play the river does not detract from the fact that he played incorrectly on both the flop and turn. 'When' he called your flop bet he was making an error because he was not getting pot odds to draw, he compounded this error on the turn.

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Not quite, he would be correct to make the 2 calls if he is getting the correct implied odds. For that to be the case he would have to be confident (and correct) to believe that you will pay off a large bet on the river if the flush hits. In the example given this is extremely unlikely given that his odds of making the flush are actually 5/1 not 4/1 on the river (there are already four clubs out). He would need you to put $9 into the pot on the river if his flush hits (before discounting for the fact that his flush may not be good, if you held a higher flush or hit a boat)

The difficulty is that as someone else said the player who calls your turn bet with a flush draw is also the player who calls down with one pair. So you have a tricky decision on the river, I would put in a standard bet (but fold to a re-raise).