$4 NLHE 6-max: Folding AA on the flop in a 4-bet pot

888 Poker $0.02/$0.04 No Limit Hold'em - 6 players

Hero (UTG): $5.56
MP: $7.73
CO: $6.41
BTN: $5.96
SB: $0.73
BB: $4.43

Pre Flop: ($0.06) Hero is UTG with
Hero raises to $0.12, MP raises to $0.21, 4 folds, Hero raises to $0.60, MP calls $0.39

Flop: ($1.26, 2 players)
Hero bets $0.71, MP raises to $1.69, Hero folds

I'm guessing this is just an awful fold. His raise on the flop was on the small side which is what worried me and I had to give him some credit when he called my 4-bet. At the time I didn't know how odd he was playing. He later made the same min 3-bet with 44 and was bluffing like a madman. I made some money back of him later when I picked of a bluff of his in a 3-bet pot.

Surely I have to just ship it here and accept that sometimes I just got coolered?

Doubt he's raising you on the flop with trip Ks as he's gonna try and extract value from you. Realistically his only 3bet/call with a K here is AK, maaaaybe KQ, but I could see raise/call from 9s-QQ

Yeah, this is a bad fold.

I agree that it is a bad fold, but it is also hard call. Here I don't think so that opponent 3bets you with KQ- it is too weak hand, maybe he has AK. Hard decision. I probably call him and I hope that I have the best hand. If he has AK, it hurts, but it happens sometimes. What a pity that he didn't play like a madman before that hand and you didn't have some reads on him before. Besides I never fold AA in heads up, with three players in pot I can fold on this board.