My main problem was establishing a range. I was pretty sure I could rule out large pockets because of the smooth call pre and on the flop. I had him on AT+, 33, 66-99, perhaps a few 45 suiteds, and a bunch of spade draws, but I had no idea what spades to place him on, which made it very hard to guess how often he'd be raising with a made hand, draw, or air. If I had played longer with him I would have had a better idea, but he was brand new and I was lost.