What is a Set-Mine?
A set-mine can be defined as follows:
“Calling a pocket pair preflop with the sole intention of flopping a set.”
By set-mining, we are not playing our pocket pair for its pot-equity or playability. If it were profitable enough to do this (as it is in many cases), it would not be correct to think of the situation as a pure set-mine.
So, for example, we cold-call with a hand like TT from the BTN vs a CO open. We are not calling purely to flop a set of Tens. On many flop textures we would expect TT to be the best poker hand, and would consider continuing against an aggressive flop action from our opponent.
If we imagine a different scenario where UTG opens, and we decide to cold-call pocket-twos in the BB, we begin to see a little closer what we mean by a pure set-mine. In the majority of cases, if our opponent fires a continuation bet on the flop, our 22 will be an automatic fold unless we spike our set. The one exception to this rule is if we flop an open-ended straight-draw and get the right pot-odds to continue.
Many preflop calls with pocket pairs will fall somewhere in between the two extremes. Most of our value might come from flopping a set. That said there are many situations where we can continue profitably with the hand, even if we don’t make our set.
How to Set-Mine Profitably
It makes sense to focus our attention on pure set-mines, where we will only make money assuming we hit our set, and lose every time we don’t. So we are pretty much going to start off by looking at the worst case scenario where our hand has absolutely no value unless we hit.
The first detail we are interested in is what percentage of the time we hit our set after calling preflop. This should give us a basic idea regarding what kind of price we might need in order for us to have a profitable set-mine. Given there are three cards on the flop, we can calculate our chances of hitting at around 11.8% of the time. In other words, based on direct pot-odds, we need to invest less than 11.8% of the total preflop pot.
But is this realistic? Not in the slightest: we will usually be investing more like 45% or the pot HU and 30% of the pot 3-way. So why is it that set-mining is considered to be a profitable strategy by many?
It all comes down to our implied odds. The preflop price does not justify a call with our pocket pair on the chance that we hit our set alone. But once we factor in the additional chips we can win when we hit our set, it can potentially become a profitable endeavour. But how much more do we need to make postflop in order for our set-mine to become profitable? And perhaps more importantly, how do we even know how much money we will make postflop assuming we hit?
Calculating Profitability of Set-Mines
Let’s start by imagining a simple preflop situation and consider how much money we would need to make on average postflop in order for set-mining to be profitable.
SB posts 0.5bb, BB posts 1bb. Action folds around to the CO, who opens to 3bb. Hero is on the BTN with a pocket pair and calls 3bb. SB folds. BB folds.
Pretty straight-forward so far. We know that we will hit with our pocket pair about 11.8% of the time, so from a direct pot-odds point of view we can’t invest more than 11.8% of the total pot. (We are not interested in pot-odds actually, only implied odds here, but we can use pot-odds to help us calculate what type of implied odds we need.)
So if 3bb equates to 11.8% of the pot, what would the total pot size need to be in order for calling to be correct.
100/11.8 = 8.475
3bb * 8.475 = 25.42bb
(In other words, if the size of the preflop pot was actually 25.42bbs and we were calling 3bb, we’d actually have a direct pot-odds call to try and hit a set. This helps us figure out how much we need to make postflop given that the actual preflop pot is a lot smaller than 25.42bb)
The total size of the preflop pot is actually 7.5bb when we include the investment from the blinds, which means we are roughly 18bb short of what we need. This is the amount we need to make postflop on average for set-mining to be profitable. In this particular scenario, it will only be around 6 times our initial investment.
Six times our investment might seem like a small enough amount to be making when we hit. However, it is not enough for it to simply be possible for us to make this amount of money when we hit. We need to be consistently making this amount of money when we hit on average. Otherwise, we will be losing money with our set-mines. There will be many situations where we hit our set and simply don’t get any action whatsoever. Therefore, we need to also rake some big pots where we make well over 6 times our preflop investment for it to be profitable overall.
We need to also consider the following scenarios
- We make our set and lose to a higher set
- We get the money in good, but villain sucks out on the river
- We think our set might not be any good and end up folding
With these scenarios factored in we need it to be possible to make significantly more than 6 times our preflop investment when we hit. If we were to make a conservative estimate, we’d ideally like for it to be possible to make almost 20 times our initial investment in the best case scenario.
The 20-times estimate gives rise to two commonly cited poker rules, the call-20 rule and the 5-10 rule.
Call-20 / 5-10 Rules
The following two rules are cited commonly by poker players. It’s a good idea to be familiar with them, even if only for the sake of being able to converse with other players.
Call-20 – We need to be able to make 20 times our initial investment after the flop
In other words, if we are investing 3bb preflop on our set-mine, we need the remaining effective stacks postflop to be at least 60bb.
5-10 – We shouldn’t invest more than 5% of our stack on a set-mining opportunity except in special circumstances where we may invest up to 10%.
We’ll get to the “special circumstances” later on, but essentially these rules are very similar. If we invest 5bb preflop with roughly 100bb effective stacks (i.e. 5%), we will be able to make roughly 20 times our initial investment postflop.
Estimating Implied Odds
It’s easy to say how much we can potentially make postflop; this is simply how deep the effective stacks are. However, there is no formula for understanding how much we will make on average. This calculation is going to be based on estimates regarding our opponent and how much implied odds we have. If we are unsure regarding our implied odds, it’s best to stick to the call-20 rule. However, in situations where we perceive our implied-odds to be very good, that call-20 rule can quickly become more like a call-10 rule.
But what exactly are implied odds? And how do we know if our implied-odds are good?
Set-Mine Implied Odds – Essentially this tells us how likely we are to get a big payout when we hit our set.
The following situations are spots where we will likely benefit from excellent implied odds.
Villain has a strong range – Hence, he is less likely to want to fold that range postflop when we connect.
Villain is aggressive – He is the type who likes to bluff a ton and may potentially try to triple-barrel bluff us when we connect.
Villain has a deep stack – The more chips villain has in his stack, the more we can potentially win.
Villain is a fish – Perhaps villain is the type that simply cannot let go of top pair when he hits. This is great for extracting value with our sets.
We can reverse this list to find situations where our implied odds are not as good as we might like.
Small Implied Odds – Even if we hit, we can’t expect a large payout.
Villain has a weak range – Villain’s range is wide, and he is more likely to fold postflop than to actually pay us off when we hit our set.
Villain is passive – Villain is the type of guy that won’t ever try to bluff us, and never makes the mistake of over-valuing second best hands.
Villain has a shallow stack – The fewer chips villain has, the less we can potentially win when we hit.
Villain is a good player – He is more likely to recognise that we are strong and make a good laydown as opposed to paying us off.
Situations with Bad Implieds
The typical situation players view as a non-profitable set-mine, despite being able to make 20 times our preflop investment, is when the BTN opens, and we are in the SB with a pocket pair.
Because BTN is opening very wide, many players feel that it is unlikely that we will get paid off postflop when hitting our set. So despite the fact that we can make 20 times our initial preflop investment a lot of players prefer to either 3bet or fold.
We must also factor in the chance that BB squeezes. If this happens, we potentially have to ditch our hand preflop, and don’t even have the chance of making our set.
This principle can also be applied to a spot where we are in MP and are facing a UTG open. Many players recommend defending only 77+ as set-mines in this spot. If we defend all pocket pairs as set-mines in MP facing a UTG open, we have the following two problems that damage our implied-odds:
- We are more likely to get squeezed and not see a flop, with 4 players still behind us. (Assuming 6-max)
- We are more likely to get set-over-set if we have a small pocket, and the flop ends up being multi-way.
Situations with Good Implieds
A very frequent question that players ask is -
Should we ever set-mine when facing a 3bet?
If we assume 100bb stacks, this situation will not fall within the call-20 rule. However, we might be able to set-mine in some cases regardless. This is the case when the 3bettor has a very strong range, increasing the chances that we get paid off when we hit. The two main situations are -
- The aggressor 3bets against an early or middle-position open, indicating he is strong.
- The aggressor has a history of only 3betting very strong holdings.
So in these scenarios it is probably correct to defend with a pocket pair against a 3bet provided -
- The stacks are at least 100bb.
- The 3bet sizing is not super large.
Another spot with good implieds might be when UTG or MP open, and we are closing the action in the BB. This is for the following reasons
- We get better direct pot-odds in the BB.
- We don’t need to worry about getting squeezed; we will always see a flop.
- UTG/MP typically have strong opening ranges, meaning that we might get paid off more frequently postflop when we hit.
Putting it Together
The important thing to take away from this is that while there are mathematical limits on when we can set-mine, most of our calculations are only as good as our estimates regarding our opponents.
The call-20 and 5/10 rules should only be used as a rough guide. It’s important in every possible set-mining situation to make an estimate regarding our opponent and how much we benefit from any implied-odds they might give us.