Since I started playing PLO a while ago, I found that this is one of the things where I frequently go wrong. I see two people betting and raising and I fold my Q-high flush, and they turn out to have a set and a straight. Or I think I pick off a bluff and run into the nuts. Example (from $25 PLO on UB):

I limp with KKQ8 in MP, LP and both blinds call. Flop is K67, two diamonds. SB min bets, BB calls, I raise pot, LP folds, SB folds, BB calls.
Turn is a 4, no diamond. BB checks, I bet pot again, BB calls.
River is a Q, no diamond. BB bets pot. I called, figuring he missed his draw. But no, he has 5789 for the straight (he had no diamonds).

Is this a stupid call? If the order of the turn and river cards was the other way around, I'd probably fold, because the straight was more obvious then. I'd also fold to a checkraise on the turn. Apparently my opponent first wanted to make sure that the flush didn't hit and the board didn't pair before investing more. Can any of the experts give me some guidelines when to call on the river with the non-nuts? This is where my biggest leak seems to be...

Any help appreciated, Pieter

This was a perfectly good river call. Looks very like he had some sort of draw to me and either tried to bluff you off it or caught something like a random set of queens or two pair, but basically i'd consider it very likely he has a bluff. I'm not laying down top set there in a month of sundays. He played this pretty horribly btw.

Smart thinking in these spots:
a) Have I seen this guy bluff before?
b) Go back through the betting on previous streets - does that river suddenly put out a draw or some other holding he might have connected with, based on earlier reads?
c) Is he loose agressive? Tight? Could he be on tilt?
d) Is this a prime bluffing situation, i.e. does the river make nothing that you could easily put him on but he's suddenly betting at it? If this is the case, has he ever slow played or not bet a nut hand (in the example you gave, if you play this guy often chances are he'll not bet his straights all the time, usually a recipe for drawout disaster in PLO).
e) what are the rough odds that he is bluffing/value betting, based on what your read might be??? Is there a 40% chance or better that you're ahead? I usually use 40% (although you only need 34-35% or so to be even money for making a call, given that you're putting in 1/3 of the chips and the rake will eat into that a little) because I like a bit of margin for error. Even if you think it's LIKELY your opponent has you beat, providing you estimate a 40% chance or more that he is bluffing or betting a weaker hand, from prior indications, you should call. In the example you gave here there is clearly well over 40% chance he is bluffing or betting a weaker hand, with no other info available.

Another quick example for you.... A recent PLO hand I played, I had 99xx and flopped middle set on a A95 board. Turn and river brought relative blanks, with a low straight possible and me holding third set. I checked and my opponent bet pot on the river. Now, I fancied he had likely turned a bigger set or caught a bizarre straight (which would've required him to play a hand containing 78 on the flop), but it was clear to me in this spot that he likely bluffs in this spot over 40% of the time (i.e. he will have a missed flush draw and no hand to beat mine, or a two-pair type hand, over 40% of the time) so I reluctantly called. In this instance I lost the pot to another dodgy slowplay (set of aces) but my thinking was generally correct and I had a well-thought out reason for making the call. 40% is your magic number.

As for making value bets on the river, I often make small value bets when I KNOW I'm ahead to offer spurious pot odds to dodgy hands that may have a piece of something. I steer well clear of hands like the one you describe (Q high flush) IF the flush was out on the flop. If you can confidently put your opponent on drawing to a hand that the river has made bigger than yours (again, 40% is the magic figure, if he makes a pot-sized raise) then you should not be calling a bet. If you hold the non-nut flush, you can always throw out a small bet to see where you are. It is a very brave PLO player who raises ME in this spot as I will often make small "pulling" bets if I DO have the nut flush, so someone who knows how I play should call and take their lumps if I have a higher flush, or fold.

Monk
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