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[RubbishCards]

Can someone who understands stud hi explain what was going on in that hand where the guy folded aces up on the river to Frangos' set of 5s? Frangos raises 5th when he catches the 5, but it is also suited to his doorcard, so I guess could be a free card play. But then he bets when checked to on 6th when the other guy makes an open pair, surely you have to either believe him and fold now or call him down. Is there a good reason to call 6th and fold 7th?