After checking on the flop. Villain has bet out $15... folded back around to me and I decide to raise.
I raise slightly more than I would have normally as I didn't want this guy calling me and pairing up to make a boat, or trying to catch a card.
So, I make it $55 to go.
He tanks for a minute or two and keeps looking back and forth between the board and me... me and the board.
He finally says out loud that if I hit it, I must be good, and shoves all in.
Board so far is:
After I call his shove, I immediately flip over my cards to show the flopped straight.
He hesitates like he doesn't want to flip his cards over.
But when he does, the table audibly gasped... almost everyone couldn't believe that he had made the play he did.
He flips over:
!!!
Two overs... with a double gut-shot.
Please don't take this the wrong way. We've all gotten our money in good on the flop only to watch someone draw out on us. It sucks and I'm sorry you didn't win. But if you don't see the value in the villain's play here, you would do well to take this hand as a lesson in learning rather than one to be frustrated by.
Villain risked ~$217 to win a $125 pot on the flop if you fold + his equity against your range with 2 overs and a double gutshot on a rainbow board to win $342 if you call. While in this particular hand it turns out he was behind when he got his money in, the fact of the matter is that not only was his play not a bad one, it was actually a profitable play. If I'm the villain here, I'm going to mix up my play between calling and shoving in this spot too.
In this particular hand, villain has 28.5% equity against your flopped straight. But your range is, or at least should be, MUCH wider than that on this board. Hero was in the blind here in an unraised pot and could easily have check raised with hands like K8, A8, 83s, 98o, basically almost any 8, T7, QT, J9, 77, T4s, AT, QJ, KJ, KQ, 66, J8, etc. Your check raising range here, especially after everyone else folded, ought to be pretty wide. And he has a strong hand against that range. He probably has at least 40% equity against your range - especially if you check raise with any naked 8. But even as played, in this worst case scenario where you actually flopped the straight, he still has 28.5% equity. That's a lot of equity for "getting it in bad".
It's easy to see why this is a profitable play if you turn it into a simple math problem. If villain has 40% equity against your range, then he doesn't even need you to ever fold for his shove to be profitable (assuming 40% equity against your range gives: $342*0.4 - $217*0.6 = +$6.60 EV). Add in the fold equity and this becomes an extremely profitable play by the villain.
But even if every single time he gets called, you rolled over 86 for the straght, giving him just 28.5% equity, that would only be a -$58 EV play for the times he gets called ($342*0.285 - $217*0.715 = -$57.685). So he'd only need for you to fold 46% of the time to break even if the entire other 54% of the time you showed him the 86 ($57.685/$125 = 0.46). But of course, he shouldn't assume that you always have the straight here. A pretty fair percentage of your check-raise holdings can't profitably call his shove, so he actually has pretty decent fold equity here. He's making a decision based on your range, and the decision he went with was a profitable play.