Heads-up on the Flop in Position: Call Flop, Raise Turn or Raise Flop

Introduction

To answer this question in the most elegant manner possible, I would like to make the following simplifying assumptions. We differentiate 2 cases:

1) We have an unbeatable hand. We want to get the most value possible.

2) We have a sure losing hand. We want to lose as little money and folding value as possible. This means we want to optimize the ratio of fold value/ cost. We are not allowed to fold before the river.

Case 1) is a simplification of a made hand, case 2) simulates a drawing hand with which we want to semi-bluff. Of course, we assume in case 2) that we are not playing against a complete maniac or an extreme calling station – in these cases we should not semi-bluff at all.



Case 2: playing a made hand

As we said, we assume that our hand is unbeatable and we are trying to extract maximum value.

Generally, one should play call flop, raise turn with made hands. In most cases you'll make an extra 3 SB, and if he calls down it could even be 7 SB. Compare that to what we would get with raise flop, bet turn; at least 1 SB to 5SB for a calldown.

If the opponent is very aggressive or the board promises a lot of action, you should go ahead and raise the flop. A very aggressive opponent often will 3-bet the flop. We will call this 3-bet and then raise the turn. Thus, we'll get 2 SB more than call flop, raise turn in case the opponent calls down.

Even if the aggressive opponent only calls our flop raise, he'll often check-raise on the turn and we'll then be able to 3-bet. This way we get 3 SB more in the case of a calldown than with call flop, raise turn.




Case 2: playing a drawing hand

Basis: Attacking the weak Spots artcle from the pro section

We assume that we are always behind and try to get the opposition to fold as cost efficiently as possible.

We first have the choice between raise flop, bet turn and call flop, raise turn.

In case 1 we saw that against a loose-aggressive opponent the chance is great that he seldom folds to a flop raise but rather often 3-bets followed by a turn bet. Even if he doesn't 3-bet, he will often check-raise on the turn.

If we play call flop, raise turn, even a loose-aggressive opponent will often fold and seldom 3-bet the turn. This means that call flop, raise turn is the better semi-bluff variant against a LAG.

Against a tight opponent it should be noted how draw heavy the board is.

If the board is draw heavy, 2 things will happen: 1. the opposition will often have some outs and 2. he will often guess that you have a draw. These two factors make it unlikely that a flop raise will be effective. In this case, you should also play call flop, raise turn.
If, however, the board has just a few or no draws (i.e. K 5 2 rainbow), then a direct flop raise against a tight opponent has a good chance of success. You have a good chance of winning the pot by investing just 2 SB. In this case, you should also raise directly on the flop.

You can even go one step further: against a very tight opponent it's enough on such a board just to call the flop. He will often play check/fold on the turn. If this opponent almost never check-raises or check-calls on the turn in such a situation then you essentially have an effective bluff for an investment of just one SB. His check on the turn indicates with great certainty that he will fold to a bet on the turn. Thus, this bet is not really a risky investment.