When an opponent opens with a raise before you, you have three options: fold, call, or re-raise. A re-raise preflop is termed a 3-bet: the big blind is the 1st bet, the open-raise is the 2nd bet, and your re-raise is the 3rd bet.
An open-raiser's range is significantly stronger than random cards. Therefore, your continuing range must be tighter than your open-raising range: a hand that is an easy open on the Button is often an automatic fold facing a raise from UTG.
Anatomy of a Balanced 3-Bet Range
A sound 3-betting strategy comprises two complementary components:
- Value Hands — QQ+, AK, and against late positions JJ and AQ. These hands welcome callers and seek to build a large pot with an equity advantage.
- Semi-Bluffs — hands too weak to profitably flat-call, but possessing excellent playability. The gold standard: suited wheel aces like A5s and A4s.
Why A5s instead of KJo? Holding an Ace provides a crucial blocker: it halves opponent combinations of AA and cuts AK by 25%, drastically reducing their 4-bet frequency. When called, A5s can flop the nut flush draw or turn a wheel straight (A-2-3-4-5). Conversely, 3-betting KJo folds out worse hands and gets called or 4-bet only by superior dominated hands.
3-Bet Sizing
- In Position — approximately 3x the open raise. Facing 2.5 bb, make it 7.5 to 8.5 bb.
- Out of Position (from the blinds) — 3.5x to 4x: make it 10 to 11 bb. Postflop will be challenging out of position, so charge a higher price and generate immediate fold equity.
If one or more players have already called the open raise before your action, increase your sizing by +1x open per caller. This multiway 3-bet is known as a squeeze: it punishes flat-callers who capped their ranges.
Calling with Pocket Pairs (Set-Mining)
Small pocket pairs rarely flop the best hand on their own. However, roughly 12% of the time (1 in 8.5 flops), they hit a set (three of a kind), which often stacks an opponent. This tactic is called set-mining.
Set-mining is only profitable with deep effective stacks. For every set you flop, you will miss roughly 7.5 times; your eventual payoff must pay for those failed attempts. Apply the practical Rule of 15-20: effective stacks must be at least 15 to 20 times the size of the preflop call. Calling 2.5 bb with 100 bb stacks (40x) is highly profitable; calling with 25 bb stacks (10x) is burning chips.
Defending the Big Blind
The Big Blind has already posted 1 bb, receiving the best pot odds at the table. If the Button opens to 2.5 bb and Small Blind folds, the pot is 4 bb and you must call only 1.5 bb:
You need only ~27% equity to break even, which justifies defending a very wide range. However, because you play Out of Position postflop, you will under-realize equity: completely unplayable offsuit junk should still be folded.