Villain is a (likely) losing reg whom I've extensive history with. Have history of him trying to bluff raise and play back at me. Loves trying to run free card plays IP with most anything that wants a freebie, though it's not impossible for him to have a hand when he jams flop.

Addendum: villain also has a history of looking me up light with any mathematical shot of being good, though he will fold made hands after I've shown clear strength.

Action: hero opens TT MP. Villain posted in CO and calls. Heads up

Flop 963r

I bet/3/5. He calls

Turn: 7 putting a second spade on board

I bet he calls

River 9 not spade

Plan?

How many spades, exactly?

Two. Let me clarify in OP

Check call

One other fun question: what's the weakest hand you five bet flop with? I have my idea but I'd be interested in the opinions of others.

K9s if you have it

Probably c/f or c/c.

Assuming he has a somewhat balanced quantity of bluff raises on this river if you bet (has he?), you should check.

If he then bets, you should give serious consideration to folding. This is pretty much the bottom of your range, so in theory this is precisely the hand to c/f (a certain percentage of the time, not 100%). Any relevant reads of course trump this.

His 4b should be polarizing -- crap looking for free cards or strong hands. Hands stronger than 9x. I don't put a lot of 9x in his 4b range. Comfortably x/c.

As we've considerably gone off the exploitative deep end with how we've played the hand (ex: if a well playing TAG posted CO, called, and raised this flop, I'd more likely call and x/r/c most turns), how much do we want to concern ourselves w/ this particular subgame optimal play of x/f at X% and x/c of (100-X)%? Since TT-AA is basically the same hand here (so theoretically, we'd like to check all 30 combos), we'd be getting 10.75:1 on a river call, so we need to be good ~ 9% (round it up due to rake). So even still, we should be calling with our TT the majority of the time (~ 55-60%) if we decide checking our overpairs is best, right?

How often is this player 4-betting a nine on the flop?

Based on the read, we know he would play 87s/87o/75s this way. Then, how likely is he to value bet those? Bluff raise river?

I think that once you go into exploitive territory, these frequencies should be abandoned. Give him a range and see how your hand stacks up against it. I'm guessing that check calling all overpairs in this spot wins the most money. Once you get a big sample on his river tendencies, you might be able to make an exploitive fold here, but without that big sample I think check calling is best.

I'm not self-advocating a river GTO style (clearly, as I'm playing about as exploitative as it gets on the flop), just that even the GTO style suggests this is a call the vast majority of time (if I opt to check this river).

I would disagree with the idea that once we deviated from GTO at a certain decision point, we should no longer be concerned with it for the rest of the hand. Here's my take on it: at some point, presumably due to a read, we decide to favor an exploitative play over GTO, but after that we enter a new subgame with its own GTO strategy, which, at the next decision point, you can again disregard in favor of an exploitative play if you have a relevant read.

For example, in this hand, if you check the river you are now essentially playing a simple game of " bluff catcher vs. bluff or made hand" with its own simple GTO strategy. As I said in the previous post, if you have a relevant read for this particular subgame, it of course trumps GTO, but otherwise it's OK to fold a certain percentage of the time. In my original post I didn't bother calculating that percentage, but it looks like you yourself did.

Speaking more exploitatively, from the description of the player you gave in the OP, it's not at all clear in which direction he would deviate from optimal play on the river. Some players would certainly bluff too much there, but others might think (often correctly): " there's no way he folds anything there". In that case, they would only bet for value and you would be wasting 1BB calling them every time. That's why, depending on the read of course, it might (or might not) be a good idea to fold.

Finally, betting the river is not out of the question either. You have a long history with this player. Do you suspect he rarely has a 9 when he 4-bets the flop? Or that he would not dare bluff raise you after this action? Will he call with a hand like 87? If so, betting becomes more attractive.

Even with given read that he sometimes will take this flop line with a value hand and no flush draws possible, I think the flop 5 bet is ok. I count 36 oesd/double gutshot draws and 31 2 pair/set combos excluding 99 because I think 99 3 bets preflop and assuming he calls preflop with 93o that maybe should be discounted.

The other nice thing about the assumption villain reraises 99 preflop is now he has to consider we can have it and that should prevent him from further punishing us when he has the best hand. I first learned this concept watching OTR15 9 bet an A95ccx flop with A9 in our 20-40 game, realizing that AA was part of his range but not part of his opponent's range so eventually opponent would have to slow down with undersets. Of course, 99 is not entirely outside our opponent's possible range here so I don't think I would 7 bet it.

Having said all that, I bet river. 45 would have probably raised the turn, 57 and 87 made a pair and will probably pay us of, 63 got counterfeited but still might pay us off. I think I'd fold to river raise since all the semibluffs now seem to have too much showdown value to turn into a bluff (they don't really have any I don't think but I think they would in villains mind-most people just don't turn pairs into bluffs. )

I like b/c river based on your reads. I'm confused as to what his flop play reduces his range to (I'm frequently confused by free carders), but we are only beat by 9x (JJ+ would 3! pre). 78 seems more likely combinatorically and intuitively.

If we could be sure he would bet river, x/c looks good, but I'd like to make sure we get a bet in on the river.

Results:

And you defeat 87