Part: Part Five - Betting Before the Flop

Flatting a three-bet

Pre-flop
Blinds 100 / 200Pot 2,600 (13 BB)CO7♠7♦● 25,000 (125 BB)YOUyou opened to 500BTN● 25,000 (125 BB)3-bettor3-bets 1,800 (9 BB)SB● 25,000 (125 BB)posts 100 (0.5 BB)BB● 25,000 (125 BB)posts 200 (1 BB)D

You open to 500 from the cutoff with 7♠7♦. The button three-bets to 1,800 and the blinds fold.

You opened pocket sevens and the button three-bets to 1,800 (9 BB). Best?

WhyCall. Pocket sevens are too good to fold but not strong enough to four-bet for value; flatting in position lets you set-mine with great implied odds and outplay him after the flop. Four-betting turns your hand into a bluff against a range that has you crushed when the money goes in.
What happensYou call. Heads-up in position.  Pot: 3,900 (19.5 BB).
Flop
Heads-upPot 3,900 (19.5 BB)7♥K♦2♣CO7♠7♦● 25,000 (125 BB)YOUa setBTN● 25,000 (125 BB)3-bettorbets 2,200 (11 BB)D

Flop 7♥ K♦ 2♣ - you flop a set. He continuation-bets.

You flopped a set in a three-bet pot and he c-bets 2,200. Best?

WhyCall. On this dry board, flatting keeps his overpairs and ace-king firing, hides your set, and sets up to stack him. Raising folds out the hands paying you off.
What happensYou call, and on the turn the money goes in - your set is far ahead.  You win a big three-bet pot.
Rather than four-bet or fold, you flatted the three-bet in position with a hand built to set-mine, then trapped when it hit. Calling three-bets in position with the right hands is its own skill.

Against a three-bet, hands like medium pairs and suited connectors often play best as in-position calls - not every spot is four-bet-or-fold.