4 left on final table. We were both short stacked for much of the final table so have tight / solid images. I had very recently taken the chip lead so did not have an overly aggressive image. No obvious post flop reads on villain but seems a solid player relative to the stakes.

My thinking:

Flop - Great for us vs villain so I sized up my cbet to get more value from weak Ax / Kx / draws.

Turn - Not ideal but I didn't want to miss value hence the barrel. Sized down a bit because I was fearing the flush a bit but tbh I'm not sure about sizing. Not sure what my plan was for the river if called tbh and perhaps should have checked back but didn't want to miss value and give a free card to a diamond holding.

When villain check raises, is this ever a bluff and are there enough bluffs in villain's range vs value (flush / A5 / K5 / 55 / maybe slow played AA and KK pre) I discounted AK-AJ as these should 3b pre? I felt villain would probably have check raised most of his non flush value on the flop to get value from my A/Kx. In fact I can't really find any bluffs other than a misplayed Kdx which should probably just call the turn since it has so much equity. My holding felt too strong to fold so I called. Given what's left behind then I should probably have just 3bet all in if I'm going to call right?

River - Whilst this card makes 55/A5/K5 less likely, is villain really shoving here for 35% pot with a missed J/T high flush or some spewy air he raised on turn? But if I call turn then should I call river?

Also, thinking about ICM - I imagine villain is going to play tighter since there are two equivalent stacks although everyone is 30 BB+ so I guess this means ICM is less of a factor because noone is imminently busting? In retrospect I should probably have folded turn. Whilst I feel this is probably too tight and exploitable, given the stakes and situation villain's nutted value to bluff ratio is so high that the fold should be profitable? I also preserve my big stack and can continue to apply pressure in other spots. As I write this I am now thinking this is an easy fold!!

PokerStars - 2800/5600 Ante 700 NL - Holdem - 4 players
Hand converted by PokerTracker 4: http://www.pokertracker.com

Hero (BTN): 68.89 BB
SB: 37.21 BB
BB: 35.56 BB
CO: 34.6 BB

4 players post ante of 0.13 BB, SB posts SB 0.5 BB, BB posts BB 1 BB

Pre Flop: (pot: 2 BB) Hero has Ts As
fold, Hero raises to 2.3 BB, fold, BB calls 1.3 BB

Flop : (5.6 BB, 2 players) Kh 5d Ad
BB checks, Hero bets 3.92 BB, BB calls 3.92 BB

Turn : (13.44 BB, 2 players) Qd
BB checks, Hero bets 6.45 BB, BB raises to 14 BB, Hero calls 7.55 BB

River : (41.44 BB, 2 players) 5h
BB bets 15.21 BB and is all-in, Hero??

Preflop
Standard open.

Flop
I dont think, this is a spot for a large C-bet. The SPR is around 7, which is definitely to much to stack off with just top pair and a somewhat mediocre kicker. Maybe you can take this sizing with AQ, where you can get value from AJ and AT, but with AT you are kind of overplaying your hand in my opinion. So I would use a smaller sizing here or even occationally mix in a check to strengten my checking range.

Turn
When the flush comes in, your hand definitely moves more towards showdown value, so the best lines now are bet turn, check back river, or check turn, call or bet a blank river. If you bet turn, it needs to be a bet-fold, because your hand is not good enough to play for stacks, and any raise will commit you to the pot. You do get raised, and rather than move all-in with less than a pot sized bet left, he essentially min-clicked giving you almost 4:1 now and almost 4:1 on a river shove. This just scream "please give me action", so I dont see, how this sizing is ever a bluff. And if it is, the way to avoid getting bluffed is to not bet the turn in the first place. So as played I would fold here.

River
The 5 was one of the best cards in the deck for you, since it reduce combos of 55 and A5, and it also mean, you now beat KQ and chop with AJ. So I guess, this is a call as played, but I would never have played the turn, the way you did, so I would never find myself in this situation. If you had checked back turn, this would be an easy call against any normal sizing.

Yeh I think I played flop/turn like we were 20BB effective. That said, given how wide our respective ranges are on the flop, does reserving large bets for nutted hands / bluffs not make us too polarised where we want him to call us pretty wide? Vs his range our hand is still better than all his Ax imo apart from maybe aj as aq should 3 bet pre?

As played I should def have folded turn to the c/r and when he bet the river I realised this and folded despite the great odds.

Saved the chips and went on to take it down anyway but this hand stuck in my memory so thought I’d sense check.

I am not that much into working with solvers and all that good stuff, so I dont actually know, what the "correct" answer to that is. But I dont see the need for using a large betsize on this kind of flop in general. A lot of hands have very low equity, like his small pairs, his suited connectors or his gutshots. And if we bet big, we just give all those hands an easy decision to fold. So personally I would just use a single sizing here, and it would be less than half pot.

No shame in realising your mistake and not throw good chips after bad. Its very easy to level ourselfes and think, he could have this or that kind of hand. But the reality of the situation is, at least 90% of the time he has a flush, and you were drawing dead on the turn