Semi-Slav Defense: Accepted Botvinnik Lilienthal
Semi-Slav Defense
Definition
The Semi-Slav is a queen-pawn opening that arises after the moves
1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6. It combines the solid pawn structure of the Slav Defense (…c6) with the flexible central set-up of the Queen’s Gambit Declined (…e6). Because Black keeps the light-squared bishop inside the pawn chain for the moment, the opening is both resilient and dynamic.
Typical Move Order & Branches
- 5.e3 — Quiet lines (Meran, Anti-Meran).
- 5.Bg5 — The most critical; can lead to the Moscow, Anti-Moscow, or Accepted variations.
- 5.Qb3 or 5.g3 — Rare but playable sidelines.
Strategic Ideas
- Black maintains a rock-solid “Slav triangle” of pawns on d5–c6–e6, preventing an early e2–e4 by White.
- The light-squared bishop’s development is postponed; it may emerge via
…b6–Bb7,…Bd6, or even stay home to guard the queenside after a future…dxc4. - Both sides fight for the central squares e4 and c4; pawn breaks with
c4–c5(White) and…c5(Black) are thematic.
Historical Notes
The Semi-Slav became fashionable in the 1920s, but its theory exploded after the 1930s thanks to players such as Mikhail Botvinnik, Vassily Smyslov and, later, Garry Kasparov and Vladimir Kramnik. It has featured in multiple world-championship matches, including Kramnik–Topalov (2006) and Anand–Topalov (2010).
Illustrative Game
Kramnik – Topalov, World Championship (ELOf 2006, Game 5) saw a razor-sharp Anti-Moscow line that ended with perpetual check after enormous complications.
Interesting Facts
- The opening’s reputation swings cyclically; whenever one side finds a new idea, theory shifts until the other side counters.
- Chess engines rank its main lines among the deepest forced variations in all of opening theory—sometimes exceeding 30 ply of “book.”
Semi-Slav Defense, Accepted
Definition
“Accepted” indicates that Black captures the queen’s-gambit pawn with …dxc4. In the Semi-Slav that capture typically occurs after White has played 5.Bg5, giving the move-order:
1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5 dxc4.
How the Variation Is Used
- By taking on c4, Black removes White’s central tension and pockets a pawn.
- Black is committed to defending that pawn with
…b5, often followed by…a6and…Bb7. - The choice invites extremely sharp play: both sides delay castling, and opposite-wing attacks are common.
Strategic Features
- Material vs. Development. Black holds an extra pawn but lags in development; White enjoys the center and open lines for the pieces.
- Pawn Structure. Black’s queenside pawns (a6–b5–c4) can become overextended; if they collapse, White’s bishops rain fire down the long diagonals.
- King Safety. Because
…g5and…h6often appear, Black’s king can remain in the center or castle long, while White aims at a king-side assault.
Historical Significance
The Accepted lines were pioneered by Alekhine and Marshall but reached theoretical maturity under the analytical microscope of Mikhail Botvinnik during the 1940s-50s.
Example Fragment
Interesting Facts
Modern grandmasters sometimes use the Accepted line as a surprise weapon: a single new engine-checked idea can overturn months of opponents’ preparation.
Botvinnik Variation (Semi-Slav)
Definition
The Botvinnik Variation is the critical and most combative branch of the Semi-Slav Accepted. Its main line runs:
1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5 dxc4
6.e4 b5 7.e5 h6 8.Bh4 g5 9.Nxg5 hxg5 10.Bxg5 Nbd7.
White sacrifices a piece for activity; Black keeps the extra material but exposes his king. The position after move 10 is one of the most analyzed in chess literature.
Strategic & Tactical Themes
- Double pawn-sacrifice. White eventually regains at least one pawn and has huge central mobility (e5, d4–d5 breaks).
- Two exposed kings. Black’s king is stuck in the middle; White’s king is uncastled on e1. Both sides calculate forcing lines deep into the middlegame.
- Critical junction. On move 11 White chooses between
11.g3(main line),11.Be2, or11.a4, each steering play into a different sub-branch.
Historical Notes
The variation is named after Mikhail Botvinnik, sixth World Champion, who used it to great effect against Keres and other contemporaries. Although Botvinnik only played the line a handful of times competitively, his extensive published analysis turned it into a fearsome theoretical weapon.
Illustrative Game
Keres – Botvinnik, USSR Championship 1941
Botvinnik uncorked novel preparation to neutralize Keres’ initiative, showcasing the variation’s depth even in its infancy.
Interesting Facts
- Garry Kasparov once called the Botvinnik Variation “the Everest of opening theory.”
- Because of its forcing nature, correspondence and engine games have mapped out many lines to move 40 and beyond—yet novelties are still found!
Lilienthal Variation (Botvinnik Semi-Slav)
Definition
The Lilienthal Variation is a sub-line of the Botvinnik in which Black develops the queen’s-bishop to b7 at an early stage. The main theoretical tabiya is reached after:
1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 e6 5.Bg5 dxc4 6.e4 b5 7.e5 h6 8.Bh4 g5 9.Nxg5 hxg5
10.Bxg5 Nbd7 11.g3 Bb7 ― Black’s 11…Bb7 marks the Lilienthal Variation.
Strategic Hallmarks
- Bishop on b7. The piece eyes the vital e4-square, challenging White’s central pawns and helping Black coordinate for …c5 or …c5-c4 breaks.
- Flexible king placement. Black can castle long or keep the king in the center, depending on how White pursues the attack.
- Long-term pawn weaknesses. Black’s kingside pawn shell (h6–g5) remains fragile, giving White tactical levers such as h-pawns pushes or sacrifices on g5/f6.
Origin & Name
Named after Andor Lilienthal, a Hungarian-Soviet grandmaster famed for defeating both Capablanca and Botvinnik. Lilienthal introduced the …Bb7 idea in the late 1930s, providing Black with a workable alternative to earlier setups.
Model Encounter
Lilienthal – Bondarevsky, USSR 1940
Though Lilienthal was on the White side, Bondarevsky adopted his opponent’s idea of …Bb7 to equalize—a charming case of the inventor facing his own creation.
Interesting Tidbits
- The variation often transposes back into mainstream Botvinnik territory after moves like
…Qb6or…c5, blurring the line between “Lilienthal” and “Botvinnik main.” - Modern engines claim the position is roughly balanced, yet game results remain volatile—perfect for daring theoreticians.