Blind Defense Fundamentals

Intermediate

Definition

Blind defense is how you respond when you're in the blinds and face a raise. You've already invested chips, so you have a discount—but you'll be out of position postflop.

Defend = Call or 3-bet vs a raise from the blinds

The Discount Factor

Big Blind Defense

Open Size Pot After Cost to Call Discount
2BB 3.5BB 1BB 1BB in already
2.5BB 4BB 1.5BB Need 27% equity
3BB 4.5BB 2BB Need 31% equity

You get better odds because you already posted the blind.

Small Blind Defense

SB faces worse odds—you only have 0.5BB invested:

Open Size Cost to Call You Need
2.5BB 2BB ~33% equity
3BB 2.5BB ~36% equity

Defending the Big Blind

Calling Range Factors

Factor Defend Wider Defend Tighter
Position of opener Late position Early position
Bet size Smaller Larger
Stack depth Deep Short
Your hand Suited, connected Offsuit, gapped

Example BB Defense Range vs BTN Open

Defend Example Hands
Always A2s+, K5s+, Q8s+, 22+, suited connectors
Often K2s+, J8s+, T8s+, suited gappers
Sometimes Offsuit broadway, weak suited

Defending the Small Blind

SB Defense Options

Action When
3-bet Strong hands, wide vs late opens
Call Some strategies allow vs BB only
Fold Default for weak hands

⚠️ Many players fold or 3-bet only from SB (no calling).

Why SB Calling is Tricky

  • BB can squeeze behind
  • You're OOP vs both players
  • Hard to realize equity

Call vs 3-Bet from Blinds

Prefer Calling Prefer 3-Betting
Speculative hands Premium hands
Deep stacks Shallow stacks
Wide opening ranges Want to end hand
Vs aggressive 4-bettors Vs calling stations

Defense by Opener Position

Opener Your Defense
UTG Tight (strong range)
MP Medium
CO Wider
BTN Widest (they open wide)

Common Mistakes

Mistake Problem
Defending too tight Giving up too much equity
Defending too loose Playing weak hands OOP
Only calling, never 3-betting Predictable, easy to exploit
Same defense vs all positions Ignoring opener's range

Key Takeaway

Defend your blinds based on the opener's position and sizing. BB gets a discount—defend wide but selectively. SB is trickier—prefer 3-betting or folding over flat calling.

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