Match Play Dynamics: Match Equity Tables, Gammon Values, and Score Tactics

Money Play versus Match Play: The Fundamental Paradigm Shift

In Money Play, each point won carries identical value, and games continue indefinitely. In Match Play (such as a 7-point, 9-point, or 11-point tournament match), points have value only to the extent that they help you reach the match target.

Surplus points beyond the threshold have zero value: winning a 4-point gammon when you needed only 1 point provides no bonus. Consequently, every checker move and cube decision in tournament play is calibrated to maximize your Match Winning Chance (MWC).

Match Equity Tables (MET) and "Away" Notation

Tournament scores are standardly tracked by how many points each player needs to reach victory (the "Away" score).

Example: In a 7-point match, if Player 1 has 5 points and Player 2 has 4 points:

• Player 1 needs 7 - 5 = 2 points (2-away).

• Player 2 needs 7 - 4 = 3 points (3-away).

• The match state is written as: "2-away, 3-away".

A Match Equity Table (MET) assigns an empirical probability of winning the match from each score configuration. Modern tournament literature widely adopts the Kazaross-XG2 Match Equity Table as the authoritative standard.

Gammon Values: Mathematical Formula and Calculations at Critical Scores

Gammon Value (VG) quantifies the value of winning a gammon relative to winning a single game. In money play, a gammon is worth 1 additional point on a 1-point game, so VG = 1.00 relative to single wins (or 0.50 if expressed as a fraction of total gammon-win points).

In match play, Gammon Value is defined formally as the ratio of extra Match Winning Chance gained from a gammon win over the equity difference between winning and losing a single game:

VG = (MWC(Gammon Win) - MWC(Single Win)) / (MWC(Single Win) - MWC(Single Loss))

Consider the following critical tournament situations calculated under the Kazaross-XG2 table:

1. Score at 2-away, 2-away with a Centered 1-Cube:

• A single win does NOT win the match. It awards 1 point, reaching 1-away, 2-away (the Crawford game), where the winner holds 69.83% MWC.

• A gammon win awards 2 points, winning the match outright (100.00% MWC).

• A single loss drops the player to 2-away, 1-away (30.17% MWC).

• A gammon loss costs 2 points, losing the match outright (0.00% MWC).

Substituting these exact values into the formula yields:

VG = (100.00% - 69.83%) / (69.83% - 30.17%) = 30.17% / 39.66% ≈ 0.761

At 2-away, 2-away with the cube at 1, a gammon is worth approximately 0.76 of a single win—substantially more than standard money value—because winning a gammon ends the match immediately and avoids the Crawford playoff.

2. Where Gammon Value is Zero (VG = 0.00):

• Double Match Point (1-away, 1-away): A single win wins the match (100.00%), and a gammon win wins the match (100.00%). There is zero incremental benefit: VG = (1.00 - 1.00) / (1.00 - 0.00) = 0.00.

• 2-away, 2-away with the Cube at 2: Here the cube is dead. A single win with the 2-cube awards 2 points and wins the match (100.00%). A gammon win (4 points) offers no extra match value: VG = (1.00 - 1.00) / (1.00 - 0.00) = 0.00.

3. Gammon-Go versus Gammon-Save (e.g. 2-away, 4-away with a 2-Cube):

• Trailer (4-away) is at pure Gammon-Go: A single win awards 2 points, bringing the score to 2-away, 2-away (50.00% MWC). A gammon awards 4 points, winning the match immediately (100.00% MWC). VG_trailer = (1.00 - 0.50) / (0.50 - 0.00) = 1.00. The trailer can take aggressive risks to pursue the gammon.

• Leader (2-away) is at pure Gammon-Save: A single loss drops the leader to 2-away, 2-away (50.00% MWC), while a gammon loss forfeits the match on the spot (0.00% MWC). The leader must prioritize safety over checker advancement.

Dead Cubes and Automatic Redoubles

A doubling cube becomes "dead" when its numerical stake is already sufficient to end the match for either player, eliminating any meaningful future redoubling options:

• Example: In a 7-point match with the score at 2-away, 2-away, once the cube is turned to 2, it is completely dead. Winning at stake 2 awards 2 points, giving the winner the match. Neither player can ever redouble to 4 constructively, because doing so adds no points that affect match outcome.

• Similarly, if a player is 1-away and the cube is at 2, redoubling is pointless for the leader since 2 points already wins the match.

• Knowing when the cube is dead allows players to calculate exact take points using dead-cube formulas rather than live-cube approximations.

Post-Crawford Strategy: Odd-Away versus Even-Away Dynamics and the Free Drop

If the trailer wins the Crawford game, the Crawford Rule expires and the doubling cube is re-activated for all subsequent games. Strategic handling depends sharply on whether the trailer’s away score is odd or even:

1. Trailer at an ODD-Away Score (e.g. 3-away, 1-away or 5-away, 1-away):

• The Trailer’s Mandate: The trailer should double on roll 1 (or very early in the game). Reason: Winning a single game at a 1-cube would earn 1 point, reaching 2-away, 1-away—leaving the trailer still needing 2 points. Winning at a 2-cube awards 2 points, propelling the trailer directly to 1-away, 1-away (DMP). Since the leader needs only 1 point to win the match in either case, doubling to 2 carries zero extra downside for the trailer.

• The Leader’s "Free Drop": When the trailer doubles at 3-away, 1-away, the leader has a one-time tactical option known as the Free Drop. If the leader drops, the trailer gains 1 point, bringing the match score to 2-away, 1-away post-Crawford.

At 2-away, 1-away post-Crawford, the leader still holds a commanding match advantage (approximately 67.5%–68% MWC under post-Crawford tables, which take into account that the cube is now active). If the leader’s winning chances in the current game are significantly below this equity threshold, passing the double preserves match equity compared to playing from a badly compromised position.

2. Trailer at an EVEN-Away Score (e.g. 2-away, 1-away or 4-away, 1-away):

• The Leader Has NO Free Drop: At 2-away, 1-away post-Crawford, passing a double immediately surrenders the match lead, bringing the score to 1-away, 1-away (DMP, 50.0% MWC). The leader cannot drop freely.

• Trailer Restraint: At 2-away, 1-away, the trailer should not double automatically on roll 1. With the cube at 1, the leader needs 1 point to win the match; turning the cube to 2 does not increase the trailer’s points needed, but gives the leader gammon leverage and surrenders the cube.