Should Muller Call Holding Fourth Pair With $300k on the Line?
Is it ever right to call with just fourth pair when facing a triple barrel during heads-up play? How about at the final table of the $10,300 GGMillion$ on GGPoker?
The hand took place between Arie Muller and Danilo Velasevic with $1,393,371 on the line. It was a very interesting call from Muller, who opted to call with just fourth pair in this hand, and was consequently incorrect.
But was this call correct according to the GTO Wizard solver? Let’s take a closer look.
Event Information:
- Event: $10,300 GGMillion$ Final Table Season 2025
- Players Left: 2
- Blind Levels: 500K/1M - 125K Ante Each
- Payouts: 1st: $1,393,371;2nd: $1,075,113
The Hand
Stack Sizes and Positions:
- Danilo Velasevic (SB/BTN): 51,836,309 (51bb)
- Arie Muller (BB): 40,363,691 (40bb)
The hand kicks off with Danilo Velasevic raising to 2,200,000 on the button with A♠3♥. Arie Muller calls from the big blind with 8♠4♠.
The flop lands A♦5♠4♥ and Muller checks. Velasevic bets 1,300,000 and Muller calls.
Muller checks again on the 10♣ turn and Velasevic bets 5,437,500. Muller calls.
Muller checks once again on the 2♠ river and Velasevic bets 18,125,000. Muller tank-calls and Velasevic wins a 53,375,000 pot with his Wheel.
Preflop Analysis
Danilo Velasevic raises to 2,200,000 holding A♠3♥. GTO Approved.
The solver recommends the SB use a 2bb opening size and mix between raising and calling with A3o. Since Velasevic opened to 2.2bb in-game, I will use the AI feature within GTO Wizard to ensure the correct number of big blinds in the pot post-flop, as this makes a significant difference to the overall strategies.
Arie Muller calls from the BB with 8♠4♠. GTO Approved.
This is a pure call with 84s, although the solver does recommend mixing in some 3-bets with hands like 85s, 64s and 74s for board protection on medium to low boards.
Both players played this spot almost perfectly pre-flop according to the solver, so let’s now analyse the post-flop action.
Flop Analysis
Flop (4,650,000 Pot): A♦5♠4♥
Muller checks. GTO Approved.
There is no donk-betting from the BB here, as the SB holds both the EV and equity advantage on this flop.
BB vs SB Range Comparison on this Flop:
Velasevic bets 1,300,000 with A♠3♥. GTO Approved.
The solver recommends a high betting frequency from the SB on this flop, with the entire range leaning towards betting. A3o is a pure bet on this board.
Recommended Strategy and EV for A3o on the flop:
When betting, the solver recommends mixing between three sizes: 28%, 41% and 60%. As shown above, all A3o combos achieve the highest EV when betting 41% or 60%, but the 28% size used by Velasevic is only slightly lower in EV, which is why his play is solver-approved.
Muller calls the 1,300,000 bet with 8♠4♠ on the flop. GTO Approved.
This is a pure call on the flop with 84s against the c-bet.
Recommended Strategy and EV for 84s on the flop:
Turn Analysis
Turn (7,250,000 Pot): 10♣
Muller checks the turn with 8♠4♠. GTO Approved.
Once again, there is no donk-betting from the BB on this turn, as the SB still holds both the EV and equity advantage.
Velasevic bets 5,437,500 with A♠3♥ on the turn. GTO Approved.
A3o is a pure bet once again on the turn, along with all other Ax combos.
Recommended Strategy and EV for A3o on the turn:
The solver recommends splitting between two bet sizes on the turn: a geometric size of 117% to set up a river all-in, and a smaller size of 74%. Velasevic used the 74% size in-game. As you can see from the EV comparisons for A♠3♥, the 117% size is actually preferred in terms of EV, but there are small mixes with the 74% size, which makes his play solver-approved.
What is a geometric bet size?
A geometric bet size is one where you bet a consistent percentage of the pot on each street so that stacks end up effectively going all-in on the river. This approach is optimal when your range is perfectly polarized, as it maximizes minimum defense frequency (MDF) while ensuring that the full stacks are committed by the river.
Muller calls with 8♠4♠ on the turn. GTO Approved.
Recommended Strategy and EV for 84s on the turn:
Although all combos of 84s now mix in some folds on the turn, calling versus this bet size with 8♠4♠ remains the optimal play, producing the highest possible EV.
84s EV on the Turn vs 117% bet size:
Interestingly, 84s is a -EV to call the turn against the 117% bet size, so Velasevic actually chose the perfect size to get maximum value from 84s here.
River Analysis
River (18,125,000 Pot): 2♠
Muller checks. GTO Approved.
Although there is now a small percentage of donk-betting on the river, 84s remains a pure check.
Recommended Strategy and EV for 84s on the river:
Checking produces significantly higher EV for all 84s combos on the river compared to betting.
BB vs SB Range Comparison on this river:
The reason the BB can now include some donk-bets on the river is that it completes certain straights, shifting equity slightly in the BB’s favor. However, only a small 11% of donk-betting occurs because the SB still holds the advantage in EV, with the best and good combos overall. This is why the solver recommends the 25% size rather than any larger sizes.
Velasevic bets 18,125,000 with A♠3♥ on the river. GTO Approved.
The solver recommends a polarised betting strategy on the river in this spot.
What is a Polarised betting strategy (on the river)?
A strategy where you bet only your very strong hands and your bluffs, while checking all medium-strength hands.
The goal is to maximize value with the best hands and apply pressure with bluffs, making it difficult for opponents to exploit your range.
You can see above in the SB’s range, this is what the solver recommends as a betting strategy on this river card.
Recommended Strategy and EV for A3o on the river:
With A♠3♥ now making a straight, it falls into the very strong hands category, so the solver recommends going all-in on the river. Velasevic’s pot-sized bet though is mixed at a low frequency, which is why it is solver-approved. In theory, the most optimal play would have been a 117% bet on the turn followed by a 117% all-in on the river. However, his in-game sizings ended up extracting maximum value from a weak hand like 8♠4♠, meaning that, from an exploitative perspective, his sizings used were nearly perfect.
The final question is: Should Muller have called 8♠4♠ on the river here according to the solver?
Muller calls with 8♠4♠ on the river vs a 18,125,000 bet. GTO Disapproved.
BB’s River Strategy vs 18,125,000 bet:
Recommended Strategy and EV for 84s on the river vs bet:
Watching this hand live, this appeared to be the biggest mistake of the entire hand, and unfortunately for Muller, the solver also agrees. Folding 8♠4♠ on the river vs this bet size is the most optimal play, with calling costing -0.18 in EV.
Strategy for Third and Lower Pairs on the river:
Above you can see that almost all third and lower pairs (aside from the top Kx combos) fold vs this bet size on the river. This shows that the BB has just enough stronger combos in their range to call this size and meet MDF.
What is MDF (Minimum Defense Frequency) in poker:
The minimum percentage of hands you must defend (call, raise, or fold less) against a bet to avoid being exploited.
If you defend less than your MDF, your opponent can profitably bluff you by betting more often.
If you defend more than your MDF, you may be over-defending and losing value with weaker hands.
Conclusion
Heads-up poker is an incredibly complex game, especially when over $300,000 is on the line. Velasevic’s decisions were straightforward in terms of hand strength on each street, yet he demonstrated both a strong theoretical understanding of the game and exploitative skill with his bet sizings, extracting maximum value from a holding that should never have called on the river. A very well-played hand from him.
Muller, despite making the biggest EV mistake of the hand by calling the river with 84s, played the rest of the hand perfectly according to the solver. This shows that he just needs to refine his river decision-making to avoid being exploited in similar spots in the future, as Velasevic did in this hand.
If you want to level up your heads-up game and learn how to avoid being exploited by other players, use the link below to download GTO Wizard for free today!
Check out the hand for yourself on YouTube, which features commentary from GGPoker ambassadors Fedor Holz and Jeff Gross.
