PokerStars - $0.10 NL FAST (6 max) - Holdem - 6 players
Hand converted by PokerTracker 4
BTN: 115 BB (VPIP: 35.29, PFR: 35.29, 3Bet Preflop: 33.33, Hands: 17)
Hero (SB): 173.6 BB
BB: 168.7 BB (VPIP: 17.48, PFR: 13.59, 3Bet Preflop: 4.00, Hands: 107)
UTG: 112.9 BB (VPIP: 27.69, PFR: 24.62, 3Bet Preflop: 9.09, Hands: 67)
MP: 120.9 BB (VPIP: 18.44, PFR: 13.69, 3Bet Preflop: 5.56, Hands: 364)
CO: 99.5 BB (VPIP: 44.00, PFR: 32.00, 3Bet Preflop: 16.67, Hands: 25)
Hero posts SB 0.5 BB, BB posts BB 1 BB
Pre Flop: (pot: 1.5 BB) Hero has T♠ A♣
fold, fold, fold, BTN raises to 3 BB, Hero raises to 10.5 BB, fold, BTN calls 7.5 BB
Flop: (22 BB, 2 players) J♦ Q♦ 3♣
Hero bets 12.5 BB, BTN calls 12.5 BB
Turn: (47 BB, 2 players) K♥
Hero bets 20.5 BB, BTN calls 20.5 BB
River: (88 BB, 2 players) 2♦
Hero bets 23.5 BB, BTN raises to 55 BB, fold
BTN wins 128.9 BB
Hi,
in general against an unknown player I do not like to 3bet especially OOP, anyway I did here, on the other hand at least gathering some information.
Preflop: So I 3bet him he calls.
Flop: As well against unknown I like to take a bit more aggressive, rather leading line. So I Cbet with a gutshot.
Turn: I might've made a mistake by Cbetting too small, I just wanted to keep him in, all draws, flushes, Kx and two pairs.
River: Very bad turn card for me. Pretty obvious his hand is and I think just makes him even stronger that he did not shove. What do you think about my river bet? May be better to bet around half pot size to make it less noticeable that this is actually a protection bet? Against a fish does not matter but a regular could notice and make me fold my better hand by shoving ...
thank you
Of course he has a flush, but not every time. He might have decided to slowplay a set until the river. Worse: He might be trying to bluff you off the hand cheaply when the 
came.