Overlap in poker
The overlap when it comes to poker has a couple of meanings. If a tournament has a guaranteed prize pool, the tournament does not get the required number of entrants to reach or exceed that prize pool, but the tournament still takes place (with the host losing), that extra money promised by the guarantee in the pool is considered the overlap.
Overlay also means extra money put into the pot, usually from a player you don’t expect to be able to continue in the hand. Let’s clarify the concept of overlap with another example.
Let’s say you’re playing in an online tournament where you start with 3,000 chips. One player opens to 800 preflop and another player goes all-in for 3000. You have a stack of 3000 chips and you wake up with AsKd. Suppose the all-in player would not bet AQ or AJ because the original raiser was in fairly early position. The betting player is also less likely to have AA or KK due to the fact that you have one of those cards. That means the most likely scenario is that you’ll have 77-QQ, starting hands that you have a little less than a 50 percent chance of winning against. Many players may fold AK to an all-in bet when putting their opponent into a pocket pair because they know they are mathematically behind. However, there is overlap. For the sake of this explanation, we’ll assume that the initial raiser won’t call unless he has pocket aces or kings, since he’ll be facing TWO all-in bets by the time the action returns to him. So, assuming he’s folding, you’ll be able to play your 3,000 chips for the 3,000 (all-in player) PLUS the 800 (initial raise) + the blinds and antes, if applicable. The 800 chips left in the pot if the initial raiser folds plus the blinds and antes would be the overlap. This additional value in the pot would be what would make it mathematically correct to go all-in even knowing that you are a bit of a loser for the all-in player.
Let’s say we put everything into our opponent squarely in the pair of queens. AK off the suit is going to be around 44 percent to win against Queens’ pair all in preflop. This means that if you went all-in for 3,000 for a chance to win 4,100 {3,000 (QQ stack) + 800 (initial raiser’s money) + 100 (small blind) + 200 (big blind)}, you would win the jackpot by 44 percent. of the time and loses it about 56 percent of the time. If you multiply the total pot of 7,100 by 44% (our chance of winning), you get an estimated chip return of 3,124. This is obviously higher than what you would have if you simply folded without having invested anything. Is a 124-chip win worth risking your tournament for? That’s a whole other post, but what you learned today is how to calculate your overlap and that it can be right to go all-in, even when you know you’re an underdog.