Establishing Range on an Opponent

I remember watching a WPT tournament a while ago where a flop with 9 high caused a player who raised pre-flop to make a big continuation bet, and the opposing player to make a big raise. The player who made the continuation bet sighed, and after a while, folded. The opposing player appeared to look at the player who folded with sympathy, and told him "There just aren't too many 9's in your range".

He had correctly established that this player was not likely to raise pre-flop if he had a hand with a 9 in it, like A 9 or 8 9. So he had guessed the bet was a continuation bet bluff, and had raised.

How was this possible?

The player who took the pot had correctly established range on his opponent.

The first way to determine range is to see how many pots a player participates in overall, and how many they raise pre flop. The more hands they participate in, the lower their range is, the lower the starting requirements for their cards are.

And the opposite holds true, with "rocks" populating the other end, the less hands they participate in, the less hands they limp or raise with, the higher their range, the higher the starting requirements for their cards are.

After establishing an overall range with player participation, you try and back up your hypothesis with actual cards, seeing if a player who raises a lot has the range you suspect, confirming a tight player has high starting hand requirements.

How do you then use this information?

If you have an A 10 on in position, and a player with a wide range limps before you, you can reasonably raise with a good degree of confidence that your hand is ahead. If however a rock in early position raises, then you have to be prepared to fold your hand, either here, or even more dangerously, when an Ace hits on the flop. Because the rocks range is so tight, the only hands they would be raising with have you beat, A J minimum, high pair probably above your kicker.

By establishing a range on an opponent, you can make informed raises or folds pre flop dependent on their actions.

Another example is with a pair of 10's. If a loose player acting before you raises, you may choose to make a big re-raise here, as a pair of 10's is ahead of much of their range. If a tight player raises, then you may still choose to call, but do so with the knowledge that they most likely have overcards to your pair...

After establishing an overall range in the first few rounds of a tournament, you start to refine that range to the situation, as peoples ranges typically lowers with position, and good players range adjusts dependent on whom they play.

I remember starting playing poker for cash and occasionally being frustrated by the fact that other hands were being won on third pair, but my top pair was either quickly being folded to, or superior hands were calling me down.

My opponents had correctly established a tighter range on me, and so knew that action from me, unlike action from some opponents, meant they were much more likely to be up against a strong hand.

Eventually you establish individual range on a player, dependent on situation and position. You then make pre and post flop choices based on your knowledge of their likely hands.

The only caveat to all of this is that sometimes loose players also get strong hands, and that, while you would normally be miles ahead calling an all in post flop on your top pair second kicker, sometimes they do have strong hands. Like all things in poker, recognize that a loose player getting a strong hand only happens occasionally, normally aggressive play with strong holdings results in profit against a looser players wider range.