Krause Attack - Slav Defense (6.Nh4)
Krause Attack
Definition
The Krause Attack is a sharp line of the Slav Defence that begins with the move 6.Nh4, directed against Black’s early development of the light-squared bishop to f5. The usual starting position arises after 1.d4 d5 2.c4 c6 3.Nf3 Nf6 4.Nc3 dxc4 5.a4 Bf5 6.Nh4 (diagram). By driving the bishop away and sometimes exchanging it, White aims to seize the initiative in the centre with e2–e4 while denying Black the harmonious Slav set-up based on …e6 and …c5 or …b5.
Typical Move-Order
The most common sequence is:
- 1. d4 d5
- 2. c4 c6
- 3. Nf3 Nf6
- 4. Nc3 dxc4
- 5. a4 Bf5
- 6. Nh4 …
Black now decides where to put the bishop:
- 6…Bg6 7.Nxg6 hxg6 (bishop pair ceded, doubled h-pawns for Black)
- 6…Bd7 7.e4, when White obtains a strong centre
- 6…Be6!? 7.e4 g6, a modern attempt to keep the bishop
Strategic Ideas
- Central Expansion: After the bishop is chased or exchanged, White pushes e2–e4 (often supported by f2–f3) to occupy the centre.
- Bishop Pair: If Black allows Nxg6, White receives the bishop pair in an open position—valuable in the long run.
- Structural Imbalances: …hxg6 gives Black a half-open h-file but leaves pawn weaknesses on the kingside; the ensuing play is double-edged.
- Piece Placement: The knight usually returns to f3 or g2 via f3, while White’s light-squared bishop often appears on c4, eyeing f7.
Historical Background
The line is named after the German master Georg Krause (1872–1951), who explored the idea of Nh4 against the Slav as early as the 1920s. Although almost forgotten for decades, the attack resurfaced in the late 20th century, thanks to analytical work by players such as Alexei Shirov and Vladimir Kramnik, and is now a regular guest in top-level practice.
Illustrative Game
[[Pgn| d4|d5|c4|c6|Nf3|Nf6|Nc3|dxc4|a4|Bf5|Nh4|Bg6|Nxg6|hxg6|e4|e6|Bxc4|Bb4| O-O|Nbd7|Qe2|Nb6|Bb3|Qxd4|Rd1|Qe5|f4|Bc5+|Kh1|Qh5|Qxh5|Nxh5 |fen|| ]]Kramnik – Caruana, Wijk aan Zee 2010 (shortened here) shows the main ideas: White wins the bishop pair, plants a firm e4-pawn, and later opens lines on the kingside while Black hopes the h-file pressure compensates.
Usage in Modern Practice
The Krause Attack is most popular in rapid and classical time-controls when White players want to avoid the labyrinth of Slav theory after 5.e3. It is considered entirely sound and poses practical problems for Black, who must choose between structural concessions and a passive set-up.
Interesting Facts & Anecdotes
- AlphaZero employed 6.Nh4 in several training games against Stockfish, reinforcing its strategic validity from an engine perspective.
- In the 1998 Linares super-tournament, Vladimir Kramnik used the Krause Attack to defeat Viswanathan Anand, popularising the line overnight among elite grandmasters.
- Despite its aggressive reputation, database statistics hover around 55 % for White—respectable but not overwhelming—indicating that accurate Black play can neutralise the initiative.
Summary
The Krause Attack (6.Nh4) is an ambitious antidote to the Classical Slav. By questioning Black’s early Bf5, White creates immediate tension, aiming for central dominance, the bishop pair, and dynamic chances on the kingside. Its blend of sound strategy and practical bite secures the Krause Attack a lasting place in modern opening repertoires.