Semi-Slav Defense: Marshall Gambit, Forgotten Variation
18K games from Lichess · Updated January 2026
White expected score · All ratings · All speeds
52.7%
the worst score you would still get, 90% confident. At best 53.3%.
Measured over 18K games at this level and clock.
A strong choice for White at this level and clock.
Outcomes for White
Draw 8.1 · Score = win + ½ of the draws · 18K games
- Rank among the families White can choose here
- not ranked — this is a variation, not a family
- Games in this context
- 18K
- Best context
- 58.5% at 1600-1799 Blitz
- Worst context
- 50.2% at 2000-2199 Rapid
- Average game length
- 38 moves
- Games that end decisively
- 91.9%
- Draws
- 8.1%
Best and worst are the strongest and weakest squares with at least 500 games behind them. The table further down shows every square, including thinner ones.
Extra Analysis
Deep-dive datasets for this opening
Where it holds · White score by rating × clock
Green is clearly ahead for White, grey is around even, red is behind. Tap a cell to measure there, and again to clear. It falls away as the rating rises: 57.1% at 0-999, 54.2% at 2500+.
| Rating | UB | Bulle | Blitz | Rapid | Class |
|---|---|---|---|---|---|
| 0-999 | — | — | |||
| 1000-1199 | — | — | |||
| 1200-1399 | |||||
| 1400-1599 | |||||
| 1600-1799 | |||||
| 1800-1999 | |||||
| 2000-2199 | — | ||||
| 2200-2499 | — | ||||
| 2500+ | — |
Expected score matrix by rating bracket and time control
- 0-999 rating, Bullet: 44.9% expected score (18 games)
- 0-999 rating, Blitz: 46.8% expected score (30 games)
- 0-999 rating, Rapid: 79.5% expected score (7 games)
- 1000-1199 rating, Bullet: 62.2% expected score (52 games)
- 1000-1199 rating, Blitz: 48.4% expected score (61 games)
- 1000-1199 rating, Rapid: 55.9% expected score (24 games)
- 1200-1399 rating, UltraBullet: 30.0% expected score (1 games)
- 1200-1399 rating, Bullet: 54.8% expected score (82 games)
- 1200-1399 rating, Blitz: 51.6% expected score (154 games)
- 1200-1399 rating, Rapid: 53.2% expected score (46 games)
- 1200-1399 rating, Classical: 50.0% expected score (2 games)
- 1400-1599 rating, UltraBullet: 78.6% expected score (2 games)
- 1400-1599 rating, Bullet: 48.8% expected score (118 games)
- 1400-1599 rating, Blitz: 58.1% expected score (326 games)
- 1400-1599 rating, Rapid: 56.0% expected score (116 games)
- 1400-1599 rating, Classical: 44.7% expected score (8 games)
- 1600-1799 rating, UltraBullet: 16.7% expected score (3 games)
- 1600-1799 rating, Bullet: 51.9% expected score (311 games)
- 1600-1799 rating, Blitz: 58.5% expected score (738 games)
- 1600-1799 rating, Rapid: 52.4% expected score (256 games)
- 1600-1799 rating, Classical: 55.5% expected score (26 games)
- 1800-1999 rating, UltraBullet: 70.0% expected score (1 games)
- 1800-1999 rating, Bullet: 54.3% expected score (598 games)
- 1800-1999 rating, Blitz: 51.2% expected score (2,136 games)
- 1800-1999 rating, Rapid: 50.7% expected score (447 games)
- 1800-1999 rating, Classical: 44.6% expected score (44 games)
- 2000-2199 rating, Bullet: 51.8% expected score (866 games)
- 2000-2199 rating, Blitz: 51.5% expected score (4,250 games)
- 2000-2199 rating, Rapid: 50.2% expected score (560 games)
- 2000-2199 rating, Classical: 45.4% expected score (20 games)
- 2200-2499 rating, Bullet: 50.3% expected score (1,168 games)
- 2200-2499 rating, Blitz: 53.4% expected score (3,849 games)
- 2200-2499 rating, Rapid: 50.9% expected score (307 games)
- 2200-2499 rating, Classical: 59.6% expected score (9 games)
- 2500+ rating, Bullet: 54.5% expected score (841 games)
- 2500+ rating, Blitz: 56.9% expected score (804 games)
- 2500+ rating, Rapid: 55.4% expected score (101 games)
- 2500+ rating, Classical: 50.0% expected score (4 games)
Related Openings
Methodology
Across every rating and clock, the Semi-Slav Defense: Marshall Gambit, Forgotten Variation scores 52.7% for White — we are 90% confident the real figure is between 52.1% and 53.3% — from 18K Lichess games. Win rate, draw rate and loss rate come from games played December 2023 to November 2025.
How the figures are made
- Whose games these are
- 18K+ rated games played on Lichess (2023-12 to 2025-11). The games are Lichess’s and free for anyone to use. What is ours is the reading of them. Last rebuilt January 2026.
- Which games we count
- Rated games only — nothing casual.
- Both players within 200 rating points of each other. A mismatch tells you about the gap, not about the opening.
- At least 2 moves played.
- A game is filed under White’s rating.
- Why every number comes with a range
- A number off a few hundred games is a guess. The same number off millions is a fact. The range is what tells them apart, and it is what the lists rank on — so an opening cannot reach the top on a lucky run of forty games. The more games behind a figure, the narrower its range.
- How much we need before we say anything
- An opening page needs 100 games. A gambit needs 50 games at a rating before we will say whether it pays there. The chaos and trap lists need 500 games overall and 250 games at one rating or clock.
Frequently Asked Questions
What is the Semi-Slav Defense: Marshall Gambit, Forgotten Variation win rate?
Playing the Semi-Slav Defense: Marshall Gambit, Forgotten Variation, White wins 48.6%, draws 8.1% and loses 43.3%. Counting a draw as half a point, that is an Expected Score of 52.7%. It rests on 18K rated games from Lichess.
At what rating does the Semi-Slav Defense: Marshall Gambit, Forgotten Variation perform best?
The Semi-Slav Defense: Marshall Gambit, Forgotten Variation performs best for White at 2500+, with an Expected Score of 55.7% (1.8K games) and the highest Floor of any rating with enough games to read.
Is the Semi-Slav Defense: Marshall Gambit, Forgotten Variation better in blitz or rapid?
For White, the Semi-Slav Defense: Marshall Gambit, Forgotten Variation scores higher in Blitz: an Expected Score of 53.0% in Blitz (12K games) against 51.7% in Rapid (1.9K games).
How sharp is the Semi-Slav Defense: Marshall Gambit, Forgotten Variation?
The Semi-Slav Defense: Marshall Gambit, Forgotten Variation has a sharpness score of 91.9 (decisive), meaning 91.9% of games end decisively. Average game length is 38 moves.
What is the Semi-Slav Defense: Marshall Gambit, Forgotten Variation win rate at 1000-1199?
At 1000-1199, White wins 51.6%, draws 6.9% and loses 41.5%. Counting a draw as half a point, that is an Expected Score of 55.1%. It rests on 137 Lichess games, which average 30 moves.
What is the Semi-Slav Defense: Marshall Gambit, Forgotten Variation win rate at 1200-1399?
At 1200-1399, White wins 50.8%, draws 3.7% and loses 45.5%. Counting a draw as half a point, that is an Expected Score of 52.7%. It rests on 285 Lichess games, which average 31 moves.
What is the Semi-Slav Defense: Marshall Gambit, Forgotten Variation win rate at 1400-1599?
At 1400-1599, White wins 53.6%, draws 4.1% and loses 42.3%. Counting a draw as half a point, that is an Expected Score of 55.7%. It rests on 570 Lichess games, which average 33 moves.
What is the Semi-Slav Defense: Marshall Gambit, Forgotten Variation win rate at 1600-1799?
At 1600-1799, White wins 54.1%, draws 3.0% and loses 42.9%. Counting a draw as half a point, that is an Expected Score of 55.6%. It rests on 1.3K Lichess games, which average 34 moves.
What is the Semi-Slav Defense: Marshall Gambit, Forgotten Variation win rate at 1800-1999?
At 1800-1999, White wins 49.5%, draws 4.2% and loses 46.3%. Counting a draw as half a point, that is an Expected Score of 51.6%. It rests on 3.2K Lichess games, which average 36 moves.
What is the Semi-Slav Defense: Marshall Gambit, Forgotten Variation win rate at 2000-2199?
At 2000-2199, White wins 48.3%, draws 6.1% and loses 45.6%. Counting a draw as half a point, that is an Expected Score of 51.4%. It rests on 5.7K Lichess games, which average 37 moves.
What is the Semi-Slav Defense: Marshall Gambit, Forgotten Variation win rate at 2200-2499?
At 2200-2499, White wins 48.5%, draws 8.1% and loses 43.4%. Counting a draw as half a point, that is an Expected Score of 52.6%. It rests on 5.3K Lichess games, which average 39 moves.
What is the Semi-Slav Defense: Marshall Gambit, Forgotten Variation win rate at 2500+?
At 2500+, White wins 41.6%, draws 28.1% and loses 30.3%. Counting a draw as half a point, that is an Expected Score of 55.7%. It rests on 1.8K Lichess games, which average 45 moves.
What is the Semi-Slav Defense: Marshall Gambit, Forgotten Variation win rate in Bullet?
In Bullet, White wins 48.2%, draws 8.3% and loses 43.5%. Counting a draw as half a point, that is an Expected Score of 52.4%. It rests on 4.1K Lichess games.
What is the Semi-Slav Defense: Marshall Gambit, Forgotten Variation win rate in Blitz?
In Blitz, White wins 49.1%, draws 7.7% and loses 43.2%. Counting a draw as half a point, that is an Expected Score of 53.0%. It rests on 12K Lichess games.
What is the Semi-Slav Defense: Marshall Gambit, Forgotten Variation win rate in Rapid?
In Rapid, White wins 46.6%, draws 10.2% and loses 43.3%. Counting a draw as half a point, that is an Expected Score of 51.7%. It rests on 1.9K Lichess games.
What is the Semi-Slav Defense: Marshall Gambit, Forgotten Variation win rate in Classical?
In Classical, White wins 42.4%, draws 12.7% and loses 45.0%. Counting a draw as half a point, that is an Expected Score of 48.7%. It rests on 113 Lichess games.
Is the Semi-Slav Defense: Marshall Gambit, Forgotten Variation a good opening?
The Semi-Slav Defense: Marshall Gambit, Forgotten Variation is good for White. Across all ratings, White wins 48.6% of its games and loses 43.3%. It performs best at 2500+. Your results depend on your rating, time control, and how well you know the typical plans.