Puzzles
#03
BB Defence
Beginner
100bb effective

Why the big blind defends widest against the button

One preflop decision with an offsuit ace in the big blind. The button opens, and the right answer is easy — what is worth learning is why this seat, and only this seat, lets you defend this wide.

  1. Pre-flop

Hand info

Seats
BB vs BTN
Street
Pre-flop
Pot
4 bb
Effective stack
100 bb
Villain raised to
2.5 bb
You already in
1 bb
To call
1.5 bb

Single raised pot, no ante. Blinds 0.5 / 1.

Pot4 BB
1
HERO ·BB
100 BB
UTG
FOLD
HJ
FOLD
CO
FOLD
2.5
D
BTN
RAISE97.5 BB behind
0.5
SB
FOLD

PREFLOP · 100BB EFFECTIVE

BTN OPEN

6-max table. Hero is BB with 100 big blinds effective. BTN OPEN. Hero holds Ah and 7c.

Hand history

Pre-flop

  • UTGFolds
  • HJFolds
  • COFolds
  • BTNRaises to 2.5 bb
  • SBFolds

It folds to the button, who opens to 2.5bb. The small blind folds. You are in the big blind with A♥7♣ — an offsuit ace — 100bb behind, and 1.5bb more to call into a 4bb pot.

What do you do?