PokerStars - 25/50 Ante 6 NL (6 max) - Holdem - 5 players
Hand converted by PokerTracker 4

BB: 30.58 BB (VPIP: 18.65, PFR: 15.01, 3Bet Preflop: 6.54, Hands: 376)
UTG: 35.06 BB (VPIP: 38.10, PFR: 28.57, 3Bet Preflop: 17.65, Hands: 44)
Hero (CO): 55.58 BB
BTN: 13.28 BB (VPIP: 14.29, PFR: 4.76, 3Bet Preflop: 0.00, Hands: 21)
SB: 45.5 BB (VPIP: 23.81, PFR: 14.29, 3Bet Preflop: 0.00, Hands: 21)

5 players post ante of 0.12 BB, SB posts SB 0.5 BB, BB posts BB 1 BB

Pre Flop: (pot: 2.1 BB) Hero has A 9

fold, Hero raises to 2.2 BB, fold, fold, BB calls 1.2 BB

Flop: (5.5 BB, 2 players) K 8 9
BB checks, Hero checks

Turn: (5.5 BB, 2 players) 9
BB bets 2.76 BB, Hero raises to 9.7 BB, BB calls 6.94 BB

River: (24.9 BB, 2 players) 3
BB checks, Hero bets 7.72 BB, BB raises to 18.56 BB and is all-in, Hero calls 10.84 BB

BB shows T A (Flush, Ace High)
(Pre 73%, Flop 98%, Turn 80%)
Hero shows A 9 (Three of a Kind, Nines)
(Pre 27%, Flop 2%, Turn 20%)
BB wins 62.02 BB

I did not see his hand coming. He didn't 3bet pre, maybe the bet on turn could give it away, but at that point I had him on Kx A8 range. Maybe it would be better in this spots to call his bet turn instead of raising but I was also didn't wanna give him another heart.

reading his stats tells me he almost never 3bets ATs
also his turn bet looks extremley suspicious for his tightness, calling would be better, and check calling river if its not a heart

Is there an argument to c-bet the flop, once checked to you? If he calls or re-raises, there's a good chance your 9 is no good. At least it gives you some information and you're likely to lose fewer chips on later streets? Pretty new, so genuine question.

There are arguments for cbetting, such as not giving draws a free card. But I prefer the check.

I would play the same pretty much the same as op but fold to the raise on river.

Clear flop cbet, ur gonna let him catch a flush with his 76o?

If he has 76 with a , he is ahead on the flop!

This is right.
Anyway to Cbet or to check the flop is opponent dependent.
I would like to see his AF and checkraise % and decide accordingly.