Very tough to put UTG on a hand. He limps then smooth calls a moderate raise. I would rule out AK. Was he limping w/ a KQ, QJ J10 spades, and if he was why the pot sized bets? Looks like someone trying to protect a big A like AQ or semibluffing w/ Ks hoping for another spade. Worst case for you he turned pocked 9 or 4 into a set on the flop.

Overall, very gutsy play. Hope you won.