Was Mariano Right to Fold an Overpair to Action Dan's River Bet?
A wild hand took place when "Action Dan" turned his pair of fives into a bluff for a huge $70,000 overbet and made popular poker vlogger Mariano Grandoli fold his overpair of pocket queens.
Is there any merit to the way both played their hands, or should they spend more time in the lab? Let’s take a look in this GTOWizard analysis.
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Preflop
Preflop was fairly standard. Mariano opened Q?Q? for $500 from the hijack, Action Dan then three-bet his A?5? to $1,800 from the Button to which Mariano responded with a $5,000 four-bet, and Action Dan called.
According to the preflop solution we solved for this hand, Mariano should mix 4-bets and calls 50/50 with queens, while Action Dan’s A?5? should call most of the time and five-bet to $13,000 around only a third of the time.
Flop
The flop was 5?3?2?. Mariano bet one-third of the pot ($3,400) with his overpair, and Action Dan called with his top pair.
Since on such a low board Mariano’s range of QQ+ remains unobstructed to bet for value across multiple streets, he should size up to two-thirds of the pot instead. He should bet any two cards due to the sheer strength of his range, capturing about 68% of the pot on average.
If Mariano had chosen the correct bet size of 66% pot ($6,900), he would be winning an extra 3,6% of the pot on average with Q?Q?.
As played, assuming Mariano bets 100% of the time for the one-third size, Action Dan should just call. We will continue the analysis with that assumption, as it’s a fair one to make.
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Turn
The turn brought in the 2?, which changed nothing. Mariano continued betting for $10,000 into a pot of $17,250 (around two-thirds pot), and Action Dan called again.
Mariano should mostly overbet 125% of the pot with most of his range, instead of betting two-thirds. The reason overbet is a better size here is that Mariano’s range is never going for thin value (88-55 and A5s/65s are semi-bluffs). The goal of his range is to get all the money in by the river, and the best way to achieve that with a polarized range is to bet an equal amount on both remaining streets (125% of the pot in this case), to maximize the opponent’s calling range. This is called “geometric” bet sizing, and you can learn more about it by reading our article on pot geometry.
After betting only roughly two-thirds of the pot on the turn, Mariano would have to bet almost 2.5x the pot on the river with his value hands, to stack his opponent. This allows Action Dan to realize his equity for a cheap price, and get away from his hand cheaply when he misses the river. If we give the solver both options (two-thirds and 125% of the pot), out of all the available overpairs only QQ with clubs will bet Mariano’s chosen size. Mariano also happened to have the club in hand, sick GTO find or happy accident? You decide! The rest of his overpairs clearly prefer the overbet as you can see in the screenshot below.
Disclaimer: Since most players will not split sizes here (due to increasing complexity with little gain), we will assume that Mariano continues with all of his value range in the $10,000 size (58% pot), and we will therefore continue under this assumption for the sake of the analysis.
As played, Action Dan should mainly continue by calling with his range, including A?5?, since Mariano’s range is extremely polar (way ahead or way behind). Only rarely should Action Dan make a big raise to get better hands to fold (about 10% of the time).
River
The river was the J?. Mariano decided to check this time, and Action Dan fired for a roughly 2x pot river bet ($70,000), putting Mariano deep into the tank for a good two minutes before mucking his hand. Let’s see how they both played the river according to theory.
Mariano’s GTO Strategy
After betting the turn for such a small size, Mariano should always bet the river for a small to medium size (one-third pot, up to two-thirds pot) with Q?Q?.
The issue with checking a hand (like QQ) that can still go for thin value is that Action Dan is going to check back weaker hands that want to see a showdown, which would otherwise often call a bet and lose. This means that whenever Mariano checks and calls a bet, the opponent’s range will be much stronger than the one Action Dan would call a bet with, putting QQ into an ugly spot. This would also allow Mariano to set the price for the river bet, instead of leaving that decision to the opponent.
It makes much more sense to find checks with nutted hands in these situations that can go for a check-raise (such as 55), to trap the strong betting range of the opponent into a much bigger pot and stack them.
According to the sim, Mariano is still allowed to check QQ without a club occasionally, as these combos don’t block Action Dan’s missed flushdraws that bluff on the river when checked to. Therefore we count his river play as a mistake, as he shouldn’t be arriving to this bluffcatching decision with his specific hand. As played, any hand that isn’t the slowplayed nuts on the river is indifferent between calling and folding when facing the jam, so we don’t blame the fold.
Action Dan’s GTO Strategy
When it checks to Action Dan on the river, his GTO betting strategy is built around good top pair or better. He should split his range between betting two-thirds of pot, or going all-in for slightly over 2x the pot. Top pair and overpairs use the two-thirds size to get some paper-thin value, while the 2x pot all-in is reserved for the crème de la crème of his range (straights & boats).
For some reason he decided to leave $25,000 behind instead of going all-in with his A?5?, but this might have been just a misread of Mariano’s stack, as he put him almost all-in. For purposes of simplicity, let’s say Action Dan went all-in on the river - it won’t make a noticeable difference to his strategy anyway.
As we can see, betting 2x the pot on the river with A?5? is definitely a good strategy, and it makes sense if we think about it a little. Since Mariano will always call the occasional AA and 55 on the river, while folding the rest at some frequency, it makes sense for Action Dan to go all-in with A5s, blocking the most important calling hands of Mariano, and unblocking his folds (underpairs 66-TT).
Sure, A5s can also check back the river and win sometimes against hands like AT or AK, but in case Mariano doesn’t construct his river range properly by fortifying it with slowplayed nuts, it should be the right thing to always go all-in with A5s in Action Dan’s shoes. The counterexploit for Mariano would be to always call his bluffcatchers on the river if Action Dan is always bluffing here.
Conclusion
Regarding preflop, we think both players played their cards right, but for postflop we can’t state the same.
Starting with Mariano, we rate his postflop play a blunder due to the many deviations regarding bet sizing and combo selection. Most of his decisions were not the most profitable possible (according to theory). Overall, he could’ve sized his bets bigger and shouldn’t be afraid to make thin river bets on rivers, although given the size of the pot of over 1,000 blinds it’s understandable for him to play it more cautiously.
Action Dan had fairly easy decisions until the turn, but his river all-in was world class and a brilliant play. Turning a hand into a bluff that can potentially check back and win is not something you will see the solver do often, so it’s surprising he found such a rare play; Well done!
The final solution can be found here and can be accessed with an active GTO Wizard Elite subscription.
