The GameMaster's Poker School
Lesson 21: Sniffing Out a Set

Let's say you're in early position at a full table, mid-way through a Sit & Go tourney and the poker gods have sent you Ace-King suited with which to play the next hand. You dutifully raise 3 or 4 times the Big Blind, which causes all but two players to fold and they just call. The flop comes A, K, 7 rainbow (all different suits). You're first to act and you lead out with a pot-sized bet, which causes one player to fold. The other player thinks for more than a few seconds as you mutter to yourself: "Stick a fork in him, he's done", but then he raises you! Your first thought is that he has made an "information" raise to see if the kicker to his Ace is good. Well, it's not, so you re-raise him. His response is to go all-in. Now what?

This could be either a very sophisticated bluff or your opponent has you beat. If it's a bluff, laying down your hand is a huge mistake and, it goes without saying (but I'll say it anyway), if he does have you beat, folding here is one of the great laydowns of your poker career. Geez, North or South. Black or White. Win or Lose. Not really much in between, is there? Sure, if you have the guy out-chipped you can call and still be in the match if he does have you beat, although you might be crippled. So, what can beat top two-pair at this point? Only one hand: Three-of-a-kind. Three Aces, three Kings or three 7s have an advantage over you, so if you can determine you're up against something other than those, life is simple again. In a cash game, it's an easy call. If he does have you beat, just reach in your pocket for more $$$. However, if losing the hand will cost you your tournament "life", it's not such an easy call.

If you were to go only by the mathematics of the situation, it's actually a good call to make. In a previous lesson, I pointed out that a pocket pair will catch a third card on the flop only about 11% of the time, so the likelihood you're up against a "set" is relatively small, especially when you're already holding two of the cards (A, K) that flopped. This is a good place to define the words set and Trips. In terms of Hold'em, a "set" is a pocket pair that has hit a third card on the board - the community cards of the hand. The term Trips means that you hold the third card of a pair that has flopped on the board. Obviously, a set is much stronger than Trips because there can be only one set of a certain rank (3s, 7s, Qs, etc.) in a hand, but there can be two sets of Trips in the same hand. Most of the time, detecting a set is much more difficult than detecting Trips, which is why we're talking about it here.

So now you're facing an all-in raise that basically has a 1-in-9 chance of being the hand that can beat you. When I encounter a situation like this, there's a checklist that I run through before I make my decision. Here it is:

1. Did I raise pre-flop? If the answer is yes, I then wonder if my opponent would stay in with a pocket pair. If the flop in our example were all low cards, I'd be less inclined to believe I was facing a set, because many - though heaven knows, not all - players will fold a "baby" pair like 2-2 to 5-5 after an opening raise from Early Position. In this case, the flop brought some face cards, so the probability that our opponent would just smooth-call our opening raise is possible. Honestly, I'd be surprised if our opponent didn't re-raise with A-A or K-K, but there are a lot of players who love to trap with a hand like that, so I probably shouldn't be very surprised.

2. Did I not raise before the flop? If I did not raise pre-flop, it's easier to believe I'm up against a set, but even there I still have some advantage on my opponent - he or she has no idea of what I'm holding. Of course, you give up some information in that regard by betting after the flop, so your opponent at least now knows you're not afraid of an Ace or King, but it's tough to put you on a hand, which may explain his "information" raise. Of course, he may not be raising in an effort to gain information, but because he believes his hand to be the best at the moment, which - if he has a set - is true. In a situation like this, I always remember that old saying, "Expect anything in an unraised pot." Be afraid, be very afraid.

3. How well do I know my opponent's game? Playing mostly online, I don't typically face a lot of "regulars" at the table, but I do take a lot of notes on my opponents, even though I may never see them again. I suppose it's fair to say that 99% of the time I have very little information about my opponent, other than what I've noticed at the table we're both at for the moment. But even a little information may be helpful; is my opponent "loose and aggressive"? If so, I might well be facing a bluff. If my perception is that the opponent is a tight player - he seldom "limps" into pots, only raises when he does come in, etc., then I'll give him or her more credit toward having a set. You get the general idea, but it's still a guess most of the time.

4. From what position did I enter the pot? If my opening raise came from Early Position, I'm more inclined to believe my opponent would call only with a larger pocket pair, like 9s or higher. Why nines? While it's really an arbitrary selection, 9-9 is the lowest of the "high" pairs, so I use them as a sort of line of demarcation (haven't used the term since 6th grade social studies). In a deck of cards, there are 13 "ranks", which begin with 2s and run up to Aces. The median card is 8; half the cards are higher and half are lower. Go ahead, run through them to be sure; I'll wait.

Got it now? As you now know, six cards lose to an 8 and six cards beat an 8. So, for our purposes here, an 8 can be considered the "average." That's why I consider 9s or higher to be above-average cards. Many players draw the line at 10s, but it basically amounts to the same thing - most will fold small pairs to a raise from Early Position. However, if I raise with the same hand from Late Position, most players will call with any pair, high or low. That's why my position is so important in solving this problem.

5. What are the dynamics of the flop? This is often referred to as the "texture" of the flop, but it all relates to which hands were helped and which hands were not helped by the three community cards. In our example, the flop was A, K, 7 rainbow, which means no player flopped a Straight or a Flush. That said, it's still possible our opponent called with Q-J and has an inside Straight draw. It's "inside" because only a 10 completes it and I would really be surprised if he or she were to go all-in with such a hand. Of course, it's not impossible; the player could be making a "semi-bluff", with the idea of either winning the pot right now or hitting the needed 10 on the turn or river. If the opponent is short-stacked and somewhat desperate, that may well be the case, but it's not likely if our opponent has an average or better chip count. Still, you cannot completely dismiss the idea because an all-in bet guarantees that our opponent will get to see both of the remaining cards. Even so, the odds are greatly against him.

Additional Considerations

These questions help me to "sniff out" a set, but I can never be 100% sure of course. That being the case, I have to then move on and see if I can win the hand. In that regard, I keep these questions in mind as the hand proceeds:

6. Can I ultimately make a hand that will beat my opponent's suspected hand? This is a critical question to ask yourself in situations like these. If you call the raise, is there a reasonable probability of making a hand that will beat a set? By "reasonable", I mean something in the 20-25% probability range, not runner-runner flush or straight cards that have a 4 or 5 % probability at best. In our example here, I can make a Full House if another A or K falls, but it also makes a Full House or better for our opponent if he does, indeed, have a set. If he has a set of 7s and another K falls, that's great for us; he'll have Sevens full of Kings and we'll have Kings full of Aces. However, if he has a set of 7s and another 7 falls, he'll have quad 7s to our Full House And so on. While holding two-pair, the probability of making a Full House with two cards to come is 16.5%. If we have three to a Flush on the flop, the probability of making a "backdoor" Flush is 6.5%. So, if we were to go all-in, which guarantees we get to see two more cards, the probability of us making a hand that can beat a set is about 23%.

7. How secure is my opponent's hand? What I mean by this is, if our opponent really does have a set, will he or she consider it to be all but unbeatable or something less than that? This is that part of the game where perception is more important than what the actual cards are. Most players with a set will approach it in a straight-forward manner, consequences be damned. They'll either re-raise as the player in the example did (although a more experienced player probably won't go all-in unless s/he's short-stacked) or they'll just call, with the idea of extracting more $$$ from us, which is probably not the best play if the dynamics of the flop allow for a Straight or Flush draw. The flop of A, K, 7 rainbow doesn't really imply that, so a call by our opponent rather than a re-raise is entirely possible. If that is how she or he responds, we're not going to think "set" right away, although we do have to keep it in mind. But, by just calling our opponent has opened the door to one more possibility for us. As I said earlier, perception matters almost as much as reality, at least until the last card is dealt. At this point, we know the best hand our opponent can be holding is a set of Aces, so we might get the opportunity to convince him that the Aces are no good. Because he only called, we get to see another card.

8. Can I convince my opponent that his hand is no good? A big part of "advanced" poker is not just the ability to read your opponent's hand; it's also the ability to make your opponent think the hand you have is somewhat different than what you're actually holding - or not. Let me explain. If you're holding a nut Straight Flush after the flop, the only way you can hope to make any $$$ on it is by convincing your opponents that you don't hold this monster of a hand. Consequently, you'll probably check or just call if someone bets into you. And I wouldn't be at all surprised if someone else does bet because the odds of anyone flopping a Flush are over 120 to 1 against, let alone flopping a Straight Flush. On the other side of the coin, you might have a hand that can be rather easily outdrawn, so you'd like to convince your opponents that drawing is futile, which you can do by making it too expensive in the form of a big bet. Here, you're all but showing your hand to the table, so you can see that being deceptive about what you hold isn't the only strategy. There will also be times when you want to convince your opponents that you hold a much stronger hand than you actually have, which is, of course, a bluff.

Going back to our original example, if our opponent just calls, we get to see another card. If that card is, say, a Queen, the board will now be A, K, 7, Q, which implies a Straight if we can convince our opponent we raised from Early Position with 10, J. I really doubt we'll be able to do that, but if the turn card is a 10, making the board A, K, 7, 10, can we convince our opponent that we raised with A-J? Of course, I have no absolute answer here because every hand will be different, but I do know this: Whether or not our opponent does have a set, the 10 on the turn very likely didn't help him and it certainly didn't hurt us; in fact we now have an inside Straight draw and maybe even a Flush draw, (which our opponent could also have.) A check by us at this point gives no information to our opponent other than making us look weak, so it could engender a big bet by him. A bet by us at this point basically implies we've improved our hand or we're bluffing. We already know we're not bluffing because we do hold top two-pair, but that doesn't beat a set, so a bet by us will likely be called, if not raised. Either a check or a bet can imply that we've made a Straight; it's all in how our opponent perceives us. If we're viewed as a player that likes to "trap", then checking is a powerful move. If we're viewed as a straight-forward player who plays only the cards we've got, then a bet is powerful. Not surprisingly, if we're viewed as a bluffer, then a bet won't have a lot of credibility with our opponent.

Again, there's no correct answer here, but if I have to choose one play, it's to bet and I much prefer to go all-in. Sure, if our opponent has a set I'm toast unless I can fill the inside straight or make a Full House, but there are several factors in my favor at this point. First of all, I do have top two-pair and that's nothing to sneeze at. Secondly, my opponent might be on a Straight draw, so an all-in bet will likely make it a very expensive call for him and third, I might hit a Straight or Full House. But even more importantly than all of those, I might be convincing my opponent that I hold something better than his set (if that's what he has.) Remember, I raised pre-flop, so I might have A-A or K-K and the only way he'd know anything different would be if he held them himself. I'll just have to take that chance. After all, luck is still a factor we cannot completely remove from the game and that's what makes it so interesting.

I'll see you here next time.