[Andy B]

Tough spot. I can see folding right away on third. Against an obvious-playing opponent in a cash game, a guy who almost has to have Kings to raise, this would probably be the best play. While knowing nothing about your opponent, it does seem a little more likely than usual that he has split Kings. First off, he doesn't have the highest door card. Secondly, the most likely "stealing" hand is a three-flush, and he can't really have one with all those diamonds out.

I can see calling as well. It is still at least somewhat likely that he's on a steal, and given the nature of tournament at this stage, it's fairly likely that no one else will call anyway. This will allow you to get away from your hand if things go south.

If you really think this guy is on a steal, then raising is probably the best play. Really, it can't be far wrong, because even if he does have Kings, you'd rather play this one heads-up, especially against a smaller stack--the only smaller stack at your table.

When he three-bets, it sure looks like you're beaten. Even so, you're pot-committed. I think that it is imperative that you make it four bets to give the Ace a chance to fold. It's better to get it heads-up as a small dog than to have to fade a third player who has the capacity to build a side pot that you don't want to play. I am somewhat amazed that he called two bets cold and then folded to a three-bet. I don't know that I've ever seen anyone do that. Well, I can think of one guy I used to play with who would do things about as irrational as that.