I played this hand as MP. I posted this to my blog and laughed how bad that opponent was. One member said that I am too evil, as opponent played it well. And for me, he made a mistake preflop and turn. At least. Then I begun to wonder how I would play that hand.
Preflop sucks imo. Dry kings, so he will flop just pair of kings for about 75% of time. Most of the time it's the overpair, some of the times it's middlepair. So oop with just problem hand for 75% flops, doesn't sound good to me. I might even fold that hand preflop, if preflop raiser isn't total fish/spewtard/monkey. And in this hand he didn't have that kind of reads.
My thoughts came from the fact that I would cbet this flop only with nuts or total air. Nuts include THE nuts and any draw that can stand check-raise. With all other draws I would take a free card. Now the problem is that the cbet is so small. If it would have been 70c, he could have check raised to $3. That would give him pot sized bet left on turn. Let's assume that opponent calls with set or flush draw. As hero doesn't know what opponent is drawing, he gets a safe turn on 60% of time.
So he is check-raising the pot at flop, and shoving any non-spade, non-pairing turn. If board pairs or spade hits, we can assume that he loses the pot. So 60% of time he will either win the pot or money goes in with about 75% favourite. 40% time he will lose the pot.
So the most horrible scenario is that opponent will call the raise with either one of the draws, and if other draw hits he will bluff at hero. And if turn is blank he will fold to a shove. In that case hero is making -EV play as he would need to win the pot about 75% of times. But I think that if opponent is drawing with a set, he won't bluff often enough if spade comes and hero checks. And I am sure that opponent will call turn shove with his draw pretty often. So my proposed line is +EV imo.
It's not the greatest line, pretty think EV spot actually. But it makes hero's life easy. Ribbo is right on there that this is the board where opponent will double barrel if turn is blank. So if flop goes with check-call, turn is a good spot for check-raising. The problem is that if opponent has just flush draw, he might check the turn too.
What does hero do if flop goes check-call, and turn is spade or pairs the board? Check-fold?