The Isolation Raise — No Limit HoldemBy
One of the basic plays that expert No Limit Holdem poker players frequently make, is to “isolate” weak or readable players before the flop. This is done by making a raise in position after the weak player limps in. The goal is to force all of the other players out, and wind up alone in the pot with the weak player, with position and the initiative. This play is known as an isolation raise, or “iso-raise”.
Depending on your skill level, you can make an iso-raise with a wide variety of hands — far weaker than your standard raising range. There are several reasons for this: First of all, your opponent is weak, and liable to have a poor starting hand himself. Secondly, since your opponent is weak, you presumably have a good read on him, and will be able to play expertly against him if he takes the flop with you. Third, you have position on him. Fourth, by raising you have taken the initiative in the hand. And finally, for all of the above reasons, your opponent is highly likely to miss the flop and simply check and fold.
That’s the biggest reason this play is so profitable. The great majority of the time, you will simply take the pot down uncontested post-flop.
A hand I recently played at Casino Matrix in San Jose illustrates how this play works. My opponent in the hand was actually not a weak player per se. He was a solid young pro. But when he limped into the pot under the gun, he made a weak play that allowed me to take advantage of him with an isolation raise. I raised it up with J♥T♥ in middle position, everyone else folded, and he decided to call. The flop came A♣9♥5♣. He checked, I bet, and he folded.
Simple, easy, and profitable. But did I just get lucky in this hand, or was it a good play? I think it was a good play, and here’s why:
From observing this opponent, I knew that when he limped under the gun he was very likely to have a small pocket pair. He could also have, perhaps, a suited A-x hand or even a suited connector that he wanted to see a cheap flop with — but this player was very tight and not on tilt, so I discounted those hands somewhat. And he might also of course be slowplaying a big hand like pocket Aces — but those hands were a very small part of his range.
I also knew that by raising the pot, I was immediately going to get a better read on my opponent’s hand. He would almost certainly re-raise a big pocket pair, and he would likely fold more speculative Ax and suited connector hands. This was a solid opponent who knows that those hands play terribly out of position against a raiser in heads up pots. So when I was called, I strongly suspected that I was against a small pocket pair, looking to flop a set.
The A♣9♥5♣ flop, although it missed my hand completely, was actually a very good flop for me. The ace hit a big part of my actual raising range in this situation, and hit an even bigger part of my “perceived range” — that is, the range that my opponent puts me on in this situation. This makes it very unlikely for him to be able to continue in the hand. So long as the 9 or 5 didn’t make him a set, I can expect an automatic fold. And that’s what I got.
One other thing worth mentioning about this play: I really like making it with a suited middle connector like JT. The reason is this: the very worst flops to standard raising hands like big pairs or AK are flops with three middle cards. Good opponents are likely to give you very little credit on these flops and make it difficult for you to continue. But hands like JT absolutely crush middle-card flops. They effectively balance your isolation raise range, and can give your opponents a very nasty and costly surprise.
And, of course, I can always represent AK any time an ace or a king flops. Like this time.