CO 20bb Defense
CO 20bb Defense
The range of hands with which a player in the cutoff position calls or raises an opponent's open-raise when holding approximately 20 big blinds in tournament play, balancing survival and chip accumulation.
Overview
CO 20bb Defense refers to the strategy of defending the cutoff (CO) position when a player has a stack of about 20 big blinds (bb) in a poker tournament. At this stack depth, the player is in a critical zone: too short to be comfortable but deep enough to retain fold equity and play postflop. The cutoff position itself is strong because it acts after the hijack (HJ) and before the button (BTN), allowing the player to steal blinds or defend against late-position raises.
Key Concepts
Stack Depth Considerations
At 20bb, the standard opening range from CO typically includes approximately 30-40% of hands, but the defending range must be tighter due to the risk of facing a re-raise from the button or blinds. The primary goal is to avoid marginal spots that could lead to elimination. Players often adopt a "jam or fold" approach, but with 20bb, there is room for limp-calling or min-raise strategies depending on opponents.
Defending Range
A typical CO 20bb defense range includes:
- Premium hands: AA, KK, QQ, AK, AQs (often re-raise to induce action)
- Strong hands: JJ, TT, AQo, ATs+, KQs, KJs, QJs (call or raise depending on opponent tendencies)
- Suited connectors: 98s, T9s, JTs (call if deep-stacked opponents allow implied odds)
- Weak aces: A9s-A2s, ATo (often fold due to reverse implied odds)
Tactical Adjustments
- Vs. early position raises: Tighten the defense range because the opener has a stronger range.
- Vs. late position steals: Widen the defense range but avoid calling with weak hands that cannot withstand a 3-bet.
- Vs. aggressive 3-bettors: Consider 4-bet shoving with premium hands or folding marginal ones.
Postflop Play
With 20bb, the stack-to-pot ratio (SPR) is low, often allowing all-in moves on flops. The defender should look for opportunities to check-raise all-in with draws or top pair, especially on coordinated boards. Avoid speculative calls that leave less than 15bb behind.
Example Scenario
Suppose you are in CO with 20bb and the HJ opens to 2.5bb. Your defense range might be:
- 3-bet shove: AA, KK, AKs, QQ (if opponent folds often to 3-bets)
- Call: JJ, TT, AQo, AQs, KQs, JTs, 99 (if opponent is passive postflop)
Conclusion
CO 20bb defense is about selective aggression. The player must balance the need to accumulate chips with the risk of busting. Exploitative adjustments against specific opponents are crucial, but a solid GTO-based foundation prevents costly mistakes.