How Significant Is ICM During Late Registration?

How Significant Is ICM After Late Registering a Tournament?

One of the many valuable aspects of GTO Wizard’s new postflop ICM feature is that we can use it at any stage of the tournament. This means that we can get a sense of how significant ICM is, even in the early portion of an MTT. I thought exploring this in the context of late registration would be interesting, given so many regulars do it.

We have already written about the ICM benefits of late registration (noteOne quick note before we get started: in the aforementioned article on late registration, I was only able to construct a toy game example of a tournament with 20 players left when I wrote that in 2023 because of limitations with ICM calculators at the time.) and the instant equity boost we receive. A $100 buy-in might be worth $110 in equity without having to play a hand, which for some players might be the deciding factor in whether they are profitable or not.

This is due to the fact that by coming in late for a tournament, we have already outlasted all the players who have been eliminated before we arrived. We start the tournament much closer to the money. We might have a slightly lower chance of winning the event outright, but we have an improved chance of making a profit. We also come in at an easier stack depth to play, because our stack-to-pot ratio is much lower, so our decisions are easier.

If max late regging tournaments is a strategy you choose to adopt, it is very important to understand how much ICM pressure is present when you enter the field.

Many players will max late reg but then play a Chip EV strategy, but as you will soon see, there is already non-negligible ICM pressure when close to half the field has been eliminated.

One quick note before we get started: in the aforementioned article on late registration, I was only able to construct a toy game example of a tournament with 20 players left when I wrote that in 2023 because of limitations with ICM calculators at the time.

Alongside the postflop ICM feature, GTO Wizard now has a huge ICM calculator where you can look at the ICM value of stacks in tournaments with up to 2,000 runners. It also has a number of prefilled payout structures you can use for tournaments with predictable numbers, like the Sunday Million. It’s a great free tool that is better than anything else out there in the market right now.

Bubble Factors

Before we jump into the strategy, let’s start with an objective measure of ICM pressure: Bubble Factor. Bubble Factor is a brilliant metric, but the name is terrible because it implies ICM pressure only matters on the bubble. This is not true, and unfortunately, I think it may have led people to assume the bubble is the only time ICM matters. In actuality, the only time when ICM does not factor into a poker tournament is heads-up, where there is only one winner-takes-all prize left to contest.

Using the 1,000-field ICM ranges from the GTO Wizard solutions library, we can see the average bubble factor at every stage of the tournament by picking the symmetrical stacks option. This is what it is at the very start of the tournament before a hand is played:

Bubble factors: first hand of a 1,000-runner MTT

It’s very low at 1.07, but it’s not Chip EV, where it is 1.

Fast forward to the actual bubble, and this is what it is:

Bubble factors: ITM-bubble of a 1,000-runner MTT

The average bubble factor for the average stack is 1.74, meaning we would need 13.5% above break-even equity to call an all-in.

We have seen perhaps the two polar opposite ends of the ICM spectrum, but what about late registration? Where does that fit in between the two extremes?

It varies depending on the site, the structures, and the format. I spent some time looking at all the major sites, and in classic tournaments, late registration would typically end with between 42 and 48% of the field remaining, so just over half the field gone. PKOs tend to see a lot more players eliminated.

Before Late Reg Ends

We don’t quite have that option in the solutions database, so let’s look at the average bubble factor with 50% of the field remaining:

Bubble factors: 50% field remaining of a 1,000-runner MTT

This would be just before late reg ends, and the average bubble factor = 1.15. This doesn’t seem dramatic; it means we would need 3.5% additional equity to call an all-in.

After Late Reg Ends

However, our next option in the database is 37% remaining, which would be a short amount of time after late reg ends (in some cases, very soon after, given all the micro-stacks who survived the bubble are in ‘spin-up mode’ and playing looser). These are the bubble factors:

Bubble factors: 37% field remaining of a 1,000-runner MTT

The average bubble factor = 1.24, meaning we need 5.3% extra equity to call an all-in. It’s starting to creep up fast.

Preflop Ranges

Before we dive into postflop strategy, we can get a sense of the adjustments by looking at the preflop ranges for the above scenarios, to see how they change. In each example, we will look at 20bb symmetrical stacks, because that’s a reasonable average stack for max late registration (it’s a lot lower on other sites).

There is no solution for 20bb stacks in the database with 100% of the field remaining, so our next best comparison is Chip EV. This is the UTG opening range alongside the BB response when it is folded to them:

UTG open & BB response: 20bb, Chip EV

This is the same spot on the bubble:

UTG open & BB response: 20bb, $EV (near bubble)

UTG can open wider because they can exert ICM pressure. However, they play fewer small pairs while adding more high card hands with more blocking power. The BB folds much more often, raises much less often and never shoves. Their raising range is much more polarized.

Now that we understand the extremes of preflop ICM, let’s see where our late registration players sit in between them. First, with 50% of the field remaining, or just before late reg ends:

UTG open & BB response: 20bb, $EV (50% field)

The UTG range is only slightly wider than Chip EV, but the shape is starting to change more towards the suited Ace-x type hands. The BB response, however, has already changed dramatically. They fold almost twice as often, raise less often, and start to shove a lot less. So, while the average bubble factor is ‘only’ 1.15, the strategy is shifting quite considerably for the defending player.

Finally, let’s look at 37% left, or quite soon after late registration ends in our example:

UTG open & BB response: 20bb, $EV (37% field)

The UTG range has started to tighten. The BB is raising at a similar frequency and split between raises and shoves. The crucial thing to pay attention to here is that they are folding almost half the time now when they folded a quarter of the time in our Chip EV estimation of the start of the tournament.

This is clear-cut evidence that:

While the bubble factors don’t appear to increase significantly, the strategy changes considerably around the late registration period.

Most notably, we defend less often and play more cautiously when we do enter the pot.

Postflop Ranges

Now, let’s look at how much postflop strategy deviates when we register late for a tournament. In this example, the stacks are 20bb with the CO opening and the BB calling. We will use the preflop ranges from the 37% of field remaining solutions from the last section in all examples. The flop is 654r.

First, let’s look at Chip EV. As you may recognize from this particular flop texture, this is the most common board type where the BB leads out a lot. Let’s look at the BB’s first action:

BB first-in flop strategy vs CO on 654r: 20bb single-raised pot, Chip EV

As you can see, the BB leads almost half the time with a mix of small, medium, and all-in bets.

Now, let’s look at the same spot, with the difference of late registering it when 48% of the field remains. The average stack is 40bb, but both our players have just come in at 20bb.

This is one of the spots where symmetrical stacks late on in a tournament are actually useful because often all the players who late register start at the same ‘alternates’ table, live and online. A player who late registers a lot is likely to be a good regular, so it’s important to get your strategy right against them.

This is the BB’s first action:

BB first-in flop strategy vs CO on 654r: 20bb single-raised pot, 48% field

Two interesting changes. First of all, the BB leads more often, ~55% of the time, compared to ~47% of the time. The bigger change, however, is the bet sizing has come down to the smallest size of 33%, rather than a mix. This is a common trend in ICM: covering players can be more aggressive and bet sizings come down.

Let’s now look at what happens when the BB checks. Firstly, in Chip EV world:

CO c-bet flop strategy vs BB: Chip EV

And then with 48% of players remaining:

CO c-bet flop strategy vs BB: 48% field

The CO is slightly more aggressive being the covering player. In this context, given both players have identical stacks, they are both the ‘covering’ player, in the sense that they can both eliminate the other. While some of the larger bet sizes are used, the bet sizings have come down on average, with the two combined smallest bet sizes being used 17.7% of the time compared to 11.8% of the time in Chip EV world.

Finally, let’s look at the response to the 33% bet size, which is the most commonly used small bet in both cases, first in Chip EV world:

BB response vs CO 34% pot c-bet: Chip EV

And then with 52% of the field gone:

BB response vs CO 33% pot c-bet: 48% field

In the ICM example, we fold a little more often, but we raise more often too. However, there is less shoving. Another interesting difference is the types of hands that raise. In Chip EV world, the nutted hands (i.e., straights) never raise in order to protect the checking range. In the ICM example, the straights raise quite often and the raising range is a lot more polarized in general.

The bubble factors in this example are 1.09, which is actually a reduction compared to the 1.15 in the 50% of the field remaining solution in the database. This is because both of our players are quite a way below the average stack, whereas in the ones we showed earlier, the players had the average stack.

Despite the fact that just 52% of the field has been eliminated and our two players’ bubble factors are just 1.09, ICM is clearly having an impact on the strategy. The frequencies are slightly deviating from Chip EV, but the main difference to take away is that the bet sizings have come way down.

Conclusion

In addition to the late registration article that I shared in the beginning, writing today’s article presented an occasion for me to revisit a very early postflop ICM article I wrote for the GTO Wizard Blog. In that article, way before this new tool was available, I made the assertion that you can see the following trends in postflop ICM:

Covering players can be more aggressive
Bet sizings go down
Solvers take low-variance lines

Even though almost half the field remains, all three of these trends showed up when we looked at postflop ICM in the context of late registration.

How significant is ICM from the moment you max late register a tournament?

While not gargantuan, it is a factor. It clearly impacts both the preflop ranges and the way we play postflop.

We should already be playing quite a lot more conservatively preflop as the defender and a little bit more aggressively as the initial aggressor who’s opening the action against covered players. Our range shifts slightly towards high cards because of their blocking power because fold equity is more valuable. Postflop, bet sizings come down across the board and we should be tighter in the face of aggression.

While the effect is small, it’s important to be aware of these strategic shifts if you are going to get into the habit of max late registering tournaments because the differences will compound over time.

What To Focus On

How to play the preflop stack depths of the late registration period because they rarely are more than 30bb and can sometimes be as low as 6bb.
However, whether it is pre- or postflop, it is probably best to include ICM in your study because it seems that the late registration period is when ICM starts to become significant!

Author

Barry Carter

Barry Carter has been a poker writer for 16 years. He is the co-author of six poker books, including The Mental Game of Poker, Endgame Poker Strategy: The ICM Book, and GTO Poker Simplified.

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