Slav Defense Variations: Modern, Alapin, Krause
Slav Defense
Definition
The Slav Defense is a family of openings that arise after the moves 1. d4 d5 2. c4 c6. Black supports the d5-pawn with the c-pawn instead of the more classical …e6 (as in the Queen’s Gambit Declined). The structure is solid, flexible, and keeps the light-squared bishop free.
How It Is Used
- Played by Black against the Queen’s Gambit to obtain a resilient pawn chain (d5–c6) and unblocked bishop on c8.
- Can transpose into numerous sub-variations: Classical Slav, Semi-Slav, Chebanenko (…a6), and others.
Strategic & Historical Significance
• Popularized in the late 19th century and refined by players such as Lasker, Alekhine, and later by top Soviet schools.
• Considered one of the most reliable replies to 1. d4 at every level, from scholastic events to world-championship matches.
• Key strategic themes include:
- Maintaining the d5-outpost and minority-attack structures (b-pawn thrust for White).
- Timely freeing break …c5 or …e5.
- Development of the light-squared bishop to f5, g4, or the modern …b6/…Bb7 plans.
Illustrative Example
1. d4 d5 2. c4 c6 3. Nf3 Nf6 4. Nc3 dxc4 5. a4 Bf5 is a main line where Black clings to the extra pawn and later plays …e6 to consolidate.
Interesting Facts
- In the 2010 World Championship, Viswanathan Anand used the Slav to neutralize Veselin Topalov’s deep preparation.
- The opening’s name comes from its early adoption by Czech and Slovak masters at the turn of the 20th century.
Modern Defense
Definition
The Modern Defense (also called the Robatsch Defense) starts with 1. e4 g6 (or 1. d4 g6) followed by …Bg7 and …d6, allowing White full central occupation while Black prepares hyper-modern counterplay.
Usage in Play
- Adopted by those seeking flexible pawn structures and transpositional tricks into the Pirc, King’s Indian, or Hippo setups.
- Favors players comfortable with unbalanced middlegames and counter-attacking chances on the central dark squares.
Strategic & Historical Notes
The defense embodies hyper-modern principles: relinquish the center temporarily, attack it later with pawn breaks (…c5, …e5) and piece pressure. Grandmasters such as Ljubojević, Ivanchuk, and Hikaru Nakamura have employed it to create complex struggles.
Example Line
1. e4 g6 2. d4 Bg7 3. Nc3 d6 4. f4 a6!? (the ‘Tiger Modern’) aims for …b5 and queenside expansion.
Trivia
- The code B06 in ECO (Encyclopaedia of Chess Openings) covers core Modern positions.
- Its alias “Robatsch” honors Austrian GM Karl Robatsch, who popularized it in the 1960s.
Alapin Variation
Definition
The Alapin Variation most famously refers to 1. e4 c5 2. c3 against the Sicilian Defense. Named after Russian master Semyon Alapin, it prevents Black’s typical …d5 or …Nf6 tactics and aims for a solid, positional setup.
Application
- Used by White to avoid open Sicilian theory and steer play into Caro-Kann-like structures.
- Black usually chooses between 2…d5 (main line), 2…Nf6, or the popular 2…e6 3. d4 d5 ‘French-like’ approach.
Strategic Value
• White builds a broad pawn center with d4 and c3.
• Typical middlegame plans include an eventual d4–d5 advance or kingside attack with f4.
• Endgame prospects often favor White due to space advantage.
Famous Encounter
Karpov – Unzicker, Nice Olympiad 1974: Karpov showcased precise maneuvering in the Alapin to convert a small edge into a win.
Fun Fact
The term “Alapin Variation” also appears in other openings (e.g., Alapin’s Variation of the French, 1. e4 e6 2. Qe2), but the Sicilian line is by far the most widespread.
Czech Defense (Czech Benoni / Czech Pirc)
Definition
“Czech” usually labels a more solid branch within an opening. Two main uses:
- Czech Benoni: After 1. d4 Nf6 2. c4 c5 3. d5 e5, Black locks the center with …e5 instead of the more dynamic …e6 (Modern Benoni).
- Czech Pirc: Arises from the Pirc Defense when Black plays …c6 and …d5, creating a compact Slav-like shell.
Usage
- Appeals to players who prefer sturdy, somewhat passive positions, aiming for counter-punches after lengthy maneuvering.
- In the Czech Benoni, Black targets queenside expansion with …a6, …b5.
Historical Context
The label “Czech” honors early 20th-century Bohemian masters (Hromádka, Gilg) who experimented with these set-ups in Carlsbad and Prague tournaments.
Example
Benoni: 1. d4 Nf6 2. c4 c5 3. d5 e5 4. Nc3 d6 5. e4 Be7 6. Nf3 0-0 produces a closed, slow-burn structure.
Krause Variation (of the Slav)
Definition
The Krause Variation arises in the Slav after 1. d4 d5 2. c4 c6 3. Nf3 Nf6 4. Nc3 dxc4 5. a4 Bf5 6. Ne5. White immediately harasses Black’s bishop and fights for e4.
Origin
Named after German master Paul Krause, who analyzed the plan of Ne5 followed by f3 & e4 as early as 1911.
Strategic Ideas
- White seeks rapid central expansion with f3 and e4, exploiting the bishop’s limited squares.
- Black can reply 6…Nbd7 or 6…e6 and must decide whether to concede the bishop pair.
Model Game
A notable modern illustration is Carlsen – Aronian, Bilbao 2012, where White’s energetic central play yielded enduring pressure.
Interesting Note
The variation is less theory-heavy than mainline 5…e6 Semi-Slav positions, making it attractive for surprise value.
Carlsbad Structure
Definition
The Carlsbad Structure is a pawn formation, not a single opening, characterized by White pawns on d4 & c4 versus Black pawns on d5 & c6 (arising from Queen’s Gambit Exchange lines, the Slav, and some Semi-Tarrasch positions).
Core Plans
- Minority Attack: White advances b2-b4-b5 to induce weaknesses on c6 and b7.
- Central Break: White prepares e3-e4.
- Black counters with kingside expansion (…f7-f5) or timely …c5.
Historical Background
Named after the 1923 Carlsbad tournament where Rubinstein, Capablanca, and others debated these structures extensively.
Classic Illustration
Rubinstein – Bogoljubov, Carlsbad 1923, showcased the textbook minority attack culminating in a winning endgame.
Anecdote
Many coaches hand students a “Carlsbad checklist,” making this structure one of the first strategic lessons taught after basic tactics.
Morozevich Variation (of the Chigorin Defense)
Definition
The Morozevich Variation revives the provocative Chigorin Defense to 1. d4: 1. d4 d5 2. c4 Nc6!? Russian GM Alexander Morozevich popularized it in the 1990s–2000s with original, fighting ideas.
Main Ideas
- Early piece activity outweighs structural defects (isolated d-pawn possibilities).
- Black often plays …Bg4, …e5, and rapid castle long.
Why It Matters
Morozevich’s successes at elite level (e.g., defeating Anand, Wijk aan Zee 2002) proved the Chigorin’s viability and injected fresh life into off-beat openings.
Sample Continuation
1. d4 d5 2. c4 Nc6 3. Nf3 Bg4 4. Nc3 e6 5. cxd5 exd5 leads to an IQP position brimming with tactical chances.
Curiosities
- Morozevich once stated he adopted the line because “the engines hated it,” giving him practical surprise value in preparation battles.
- The ECO code for this branch is D07.