100bb Bubble Play

Overview

100bb Bubble Play refers to the strategic considerations in a poker tournament when the stack depth of players is around 100 big blinds (bb) and the tournament is approaching the bubble—the point just before players begin cashing. At this stage, the Independent Chip Model (ICM) significantly impacts decision-making, as finishing just outside the money is costly. However, with 100bb stacks, players have room to maneuver post-flop, unlike in shallow-stack bubble situations.

Key Concepts

ICM Pressure

ICM assigns a monetary value to each chip based on tournament payout structure. Near the bubble, each chip is worth more than its face value because losing all chips means busting without prize money. With 100bb, the risk of elimination is reduced compared to short stacks, but still players must avoid unnecessary confrontation, especially against big stacks that can bust them.

Adjusted Ranges

• Opening Range: Typically tighter than in early stages but wider than with 30bb stacks. Players can open more hands but should fold to re-raises if opponents show strength, particularly from short stacks who are desperate to double up.
• 3-bet and 4-bet Range: Should be polarized; value hands and bluffs. Avoid 3-betting marginal hands as opponents may exploit ICM fear.
• Calling Range: Defend the big blind wider than usual because stacks are deep, but avoid calling raises that commit a large portion of chips. Folding to bets with weak hands is often correct due to ICM.

Post-Flop Play

With deep stacks, post-flop skill becomes crucial. Players can use large bets to apply ICM pressure on opponents. For example, a big stack can put smaller or medium stacks to difficult decisions by betting 3/4 pot or overbetting. Conversely, medium stacks should avoid building large pots without strong holdings.

Bubble Dynamics

• Short Stacks: Those with less than 20bb often shove or fold. They are desperate to double up and will call lighter in their big blind at low risk.
• Medium Stacks (30-60bb): Must be cautious. They can pressure short stacks but should avoid battling big stacks without a strong hand.
• Big Stacks (100bb+): Have the most flexibility. They can raise liberally, 3-bet often, and put opponents to tough calls. However, they also need to avoid getting into large pots with another big stack that could cripple them.

Example Scenario

In a $10+1 tournament with 10 players remaining (8 paid), you have 100bb on the button. The small blind has 90bb, big blind has 25bb. It folds to you. ICM suggests you should open a standard range (e.g., 22+, A2s+, K9s+, A9o+) but be prepared to fold to a big stack's 3-bet if you hold a marginal hand. The big blind short stack may shove; you can call with top hands but avoid risking a big pot with a hand like K6s.

Conclusion

100bb Bubble Play requires a balance of ICM awareness and deep-stack skills. Players should tighten against raises, pressure short stacks, and avoid unnecessary risks against other big stacks. Understanding opponent stack sizes and tendencies is key to maximizing expected value.