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PokerStars No-Limit Hold'em Tourney, Big Blind is t400 (2 handed) FTR converter on zerodivide.cx

Button (t8775)
Hero (t4725)

Preflop: Hero is BB with A[img]/images/graemlins/spade.gif[/img], 3[img]/images/graemlins/spade.gif[/img].
<font color="#CC3333">Button raises to t800</font>, Hero calls t400.

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That's sort of strange pre-flop action, isn't it? A min-raise and no push with A3s?

I suspect villain made a stab at the pot when you checked twice, but will give up pretty easily to the all-in on the river. I don't really think he has an ace, at least not a mediocre one, if he has previously been aggressive about stealing blinds -- maybe he min-raised with a big ace? If he did, he ain't folding now. He'll probably fold other pairs, and he'll call, of course, with two pair. I don't think the river all-in does anything for you.