Thats a loaded question man. You have to know your opponent and play according to his style. A specific hand would make it easier to understand for the readers.
ST SnG $1.00, blinds up every 6 minutes
Hero (BU) 20 BB
Villain (BB) 35 BB
Hero has Jh9h
Pre flop: Fold, fold, Hero raises 2.25x, fold, Villain calls from BB.
Flop comes: 5s9sQh (pot 5 BB)
Villain bets 40% of the pot (2BB).
Hero: ?
A call here pretty much will lead to another 2 or 3 rounds of betting. Even if the villain is likely to have the worse hand or a drawing hand, a call here, pretty commits Hero to the pot, so it's very likely that a donk bet will come with a turn bet. Villain's only hand that could beat Hero are pocket 5s, 59, K9, A9 or Qx. Unlikely Villain has 99, TT or better, villain would three bet pre flop. I think hands like KQ and AQ hero would 3-bet pre flop. That's where my doubt really resides. I think folding to donk bet is pretty passive and exploitable by experient players.
It's really a narrow range, most of his range is a flush draw or a straight draw, that you beat. But he has you covered.
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Look the outcome of this hand.
Hero calls bet of 40% of the pot on the flop.
Turn: 7d (pot 9 BB). Villain bets 3 BB. Hero calls.
Figured out villain was semi
bluffing a draw most of the time. Only draw that hits is T8. If my hand was good on the flop, most of the time it's still good on the turn.
River: 7h (pot 15 bb). Villain bets 4 BB. Hero calls.
Figured out it was a pretty polarizing bet, either value bet, or a missed draw
bluff. His sizing is imo of a value bet. Expecting calling stations on microstakes to call. The ONLY hand that improved from the turn is a seven. I don't expect any seven in villain's hand. He is repping a set of fives, a queen or two pair. Unless he's a maniac value betting his bottom or middle pair.
Villain shows As7s -- three of a kind (ace kicker).
Hero shows Jh9h -- two pair (nines and sevens, Q kicker)
Villain was semi-bluffing flop and turn streets but caught trips on the river. Of course I'd have folded to overcards to my nine that doesn't improve me, and any spade.
Did I play it ok? The question that raises to me is: is it good to donk bet on a flopped draw? Is it good to call a donk bet with second pair? Are
hands like these (obviously taking out the running cards), happening often?