Techniques for Spotting Back Door Flushes Especially in 3-Bet Pots

It is important to pay attention to the distribution of suits on the flop when doing proper hand reading, especially in a 3-bet pot when your opponent suddenly wakes up on the river representing a backdoor flush.

Posted Nov 28, 2021

When dealing with playing 3-bet pots a lot of players have difficulty with hand reading. Players are far more comfortable in single raised pots because the situations are more common. Even if you only get involved with a few 3-bet pots per session sometimes they make up the largest pots of the night.

Let's take a look at the following example. Even though the following spot bizarre it was an actual hand that took place on the TCH Live stream here: How to Spot a Backdoor Flush (Poker Tip)

$1/$3/$6 No Limit at Texas Card House

UTG +2 raises to $30 with 8 4 , HJ 3-bets to $100 with K 3 .

SB cold calls with A J , UTG +2 calls.

FLOP: K 3 8 ($309).

HJ c-bets $200, SB calls, UTG +2 folds.

TURN: K ($709).

HJ bets $300, SB calls.

RIVER: 2 ($1,300).

SB leads for $550, HJ shoves for $1,300.

Preflop Dynamics and Action:

As you can see this game was extremely loose. UTG+2 raises with 8 4 , gets 3-bet with K 3 from the HJ, and the SB cold calls. Typically, it’s not the best idea to cold call 3-bets because the initial raiser still has the opportunity to 4-bet. This becomes less of an issue if you know that the preflop raiser is very unlikely to 4-bet unless he has a hand like AA or KK (which can be common in live no limit), and in situations like this you can exploitatively flat 3-bets more often. If the SB is aware of how loose these players are playing, he should probably just be 4-betting the A J as it will almost always be a profitable decision given the game dynamics.

Flop Analysis:

The flop is K 3 8 ($309), giving SB the nut flush draw, UTG +2 middle pair, and HJ two pair. The action checks to the preflop 3-bettor (HJ), who c-bets a large, with 2/3 pot sizing. This is probably a little too big, especially holding a king. People will be less likely to continue given that he holds a king himself, and a smaller size could get more action from hands like 8 4 for second pair. When HJ bets this size SB should really only be continuing when he has a king or the nut flush draw, given the fact that he’s in the worst position with UTG +2 left to act. This information is very important especially since there’s no straight draw on the board.

Turn Analysis:

The turn brings another king, making the board K 3 8 K ($709). HJ and SB are still both very deep stacked with around $1,600 effective. This means that for HJ, to get all of the money in the middle with K 3 , needs to bet both turn and river. Since we put SB on a king, set or the nut flush draw on the flop, we know that he should have a full house that we beat, trip kings or a hand like the nut flush draw. So the HJ should absolutely bet again, which he does for $300 which sets him up nicely for a river all in.

River Analysis:

The river brings in the backdoor flush draw, giving us a board of K 3 8 K 2. At this point SB should just be giving up. HJ has a fair number of kings and his range is weighted towards value in general. Even if HJ somehow barreled the turn with a hand like QQ, is he really going to fold on the river when the front door flush draw bricks? This is definitely a spot where HJ is going to have a ton of value combos, and SB should just be giving up. But that doesn’t happen. SB leads out for $550, basically trying to represent a full house or a backdoor flush.

Obviously HJ can just jam all in over this bet because he beats pretty much all of SB’s value combos, but there is a lot that we can learn here based on the board texture in this hand. The SB's bluff simply doesn’t make any sense since he cannot credibly represent the backdoor flush draw. When someone makes an aggressive action to represent a backdoor flush you must go back to the flop and look at the distribution of suits. Here, on the flop, we have K 3 8 , meaning that for someone to credibly have a backdoor flush draw they would have to have top pair with backdoor diamonds, K x He can’t have middle pair with backdoor diamonds because the eight is a diamond, and there are no straight draws that SB could have. When the turn brings the K , this also means that the SB also cannot have top pair with the backdoor.


When someone is trying to lead out and represent a flush on the river, remember to go back to the flop texture and properly understand the suit distribution. Thinking through these situations and narrowing your opponents' range is critical, since you won’t always have the nuts when you get led into on the river.

If you enjoyed this breakdown and would like to listen to Bart dissect the hand in depth, you can head on over to the Crush Live Poker YouTube Channel and watch the full video, available by clicking on the link here.

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