On this particular flush-completing turn, Chris recommends polarizing your range. Here's what such a betting range would contain

• The nut flush and second nut flush at a high frequency.
• Hands that retain robustness of equity (more on this in a moment).
• Bluffs that contain a spade, especially hands with the A♠ blocker.

What does it mean for a hand to retain robustness of equity? It means the hand maintains its equity on various run-outs versus the opponent's continuing range. On this board, the prime candidates are sets, with top set being bet at a high frequency and middle/bottom set mixing bet and check.

When he check-raises, mjparry is representing the nut flush. Here's what Chris had to say about this spot:

This is a good time to ask ourselves if any of the actions in this hand have led him to be discounted in the number of nut flushes versus nut flush blocker combinations he can have in his range.

And I think the answer to that question is "yes, one of those hand classes is going to be discounted."

If we think back to the flop action, remember, we bet the flop. So we are going to have most or close to all of our nut flush combinations, but our opponent check-called the flop. Sure, he is going to check-call some of his nut flush combinations, but the majority of them are going to lean towards raising on the flop.

Chris goes onto say that running this spot in a solver confirms his expectation that mjparry should indeed be discounted in the number of nut flushes he has here versus nut flush blockers. Specifically, mjparry should have the nut flush blocker about 1.5 times more often than the nut flush going into the turn.

So this is a spot where mjparry has to be selective with which nut flush blockers he chooses to bluff. This is because if he check-raises all of them on the turn and follows through with all of them on the river, he will be bluffing far too often.

Going back to that robustness of equity concept for a moment, here's another quote from Chris I want to share with you:

As this hand is playing out we see why there is so much emphasis on betting hands in position that have robustness of equity.

We much prefer to be in a situation like this where we have a set and if we are behind, we have some outs to the effective nuts. [Compare this] to having a hand like a middling flush, which is a pure bluff-catcher that can not catch up on the river.

With one out to the nuts and nine outs to the effective nuts, Chris has an easy call versus the check-raise. To the river!