Openings

Four Knights Game - Spanish Variation

A symmetrical opening where both sides develop knights early, leading to rich positional play with the bishop pair.

Try Interactive Lesson

Introduction

The Four Knights Game is one of the oldest chess openings, dating to the 16th century. Both sides develop their knights symmetrically before the position sharpens. The Spanish Variation (4. Bb5) mirrors the Ruy Lopez idea, and after 4. ..Bb4 the Double Spanish arises — one of the most balanced structures in chess. This opening experienced a major revival at the highest level. Carlsen, Nepomniachtchi, and Grischuk have all employed it in elite events. White aims for the bishop pair after the ..Bxc3 exchange, accepting doubled pawns for long-term piece activity. The resulting positions are rich in strategic nuance — White's bishops versus Black's superior pawn structure.

Lesson Content

8
7
6
5
4
3
2
1
a
b
c
d
e
f
g
h
View on Analysis Board
1. e4

The King's Pawn opening — White claims the center and opens diagonals for the queen and kingside bishop. The most popular first move in chess. Black's main responses: - 1. ..e5 — Open Game, matching White's center - 1. ..c5 — Sicilian Defense, fighting for d4 asymmetrically - 1. ..e6 — French Defense, preparing ..d5 - 1. ..c6 — Caro-Kann, also preparing ..d5

Center ControlDevelopment
Alternative Moves
d4 — Also excellent, but leads to different openings. e4 is sharper and leads to the Four Knights.
1
2
3
4
5
6
7
8
h
g
f
e
d
c
b
a
1. ..e5

Black mirrors White's central claim, establishing a symmetrical pawn center. This leads to the Open Games — the oldest and most classical family of openings. The e5 pawn controls d4 and f4, limiting White's expansion options.

Center Control
8
7
6
5
4
3
2
1
a
b
c
d
e
f
g
h
2. Nf3

White develops the knight to its most natural square, attacking the e5 pawn immediately. The knight also controls d4 and prepares kingside castling. This is the most common second move, leading to a vast tree of openings including the Italian, Ruy Lopez, and Scotch.

DevelopmentThreat
1
2
3
4
5
6
7
8
h
g
f
e
d
c
b
a
2. ..Nc6

Black defends the e5 pawn with the most natural developing move. The knight on c6 also controls the important d4 and e5 squares. From here White's third move defines the opening: - 3. Bc4 — Italian Game - 3. Bb5 — Ruy Lopez - 3. d4 — Scotch Game - 3. Nc3 — Four Knights / Vienna hybrid

DevelopmentCenter Control
8
7
6
5
4
3
2
1
a
b
c
d
e
f
g
h
View on Analysis Board
3. Nc3

White develops the second knight symmetrically, entering the Four Knights Game (ECO C47). Rather than committing a bishop immediately, White reinforces control of d5 and e4 while keeping options open. This is a flexible choice — White delays the bishop development to see how Black responds: - 3. ..Nf6 — the pure Four Knights - 3. ..Bb4 — a Nimzo-like setup - 3. ..d5 — the Scotch Four Knights

DevelopmentCenter Control
Alternative Moves
Bc4 — The Italian Game — targets f7 directly. Nc3 is more restrained, developing without committing the bishop.
Bb5 — The Ruy Lopez — also excellent but leads to completely different structures.
1
2
3
4
5
6
7
8
h
g
f
e
d
c
b
a
3. ..Nf6

Black completes the symmetry — all four knights are developed. This is the defining position of the Four Knights Game. Black attacks e4 while developing naturally. The position is one of the most balanced in opening theory, with 17,000+ master games from this exact setup.

DevelopmentThreat
8
7
6
5
4
3
2
1
a
b
c
d
e
f
g
h
View on Analysis Board
4. Bb5

The Spanish Variation — White puts pressure on the Nc6, echoing the Ruy Lopez idea within the Four Knights framework. This is the most popular choice at master level (7,000+ games, avg rating 2409). White's alternatives lead to distinct variations: - 4. d4 — Scotch Four Knights, immediately opening the center - 4. g3 — Glek System, a hypermodern approach - 4. Bc4 — Italian Four Knights, targeting f7

DevelopmentPiece ActivityThreat
Alternative Moves
d4 — The Scotch Four Knights — active but leads to heavy simplification and a drawish reputation.
g3 — The Glek System — flexible but slower. Bb5 creates immediate tension.
1
2
3
4
5
6
7
8
h
g
f
e
d
c
b
a
View on Analysis Board
4. ..Bb4

The Double Spanish! Black mirrors White's pin, creating maximum symmetry. Both bishops pressure the opposing knight — Bb4 targets Nc3 and Bb5 targets Nc6 — though the d-pawns currently block a direct pin to either king. Black's key alternatives: - 4. ..Nd4 — the Rubinstein Variation, an aggressive pawn sacrifice - 4. ..Bc5 — Classical Variation, avoiding the symmetrical tension - 4. ..Bd6 — a modern try favored by Carlsen as Black

DevelopmentPiece Activity
Alternative Moves
Nd4 — The Rubinstein — dynamic but risky. Bb4 maintains the solid symmetrical structure.
8
7
6
5
4
3
2
1
a
b
c
d
e
f
g
h
View on Analysis Board
5. O-O

White castles early, securing the king and activating the rook. With the symmetrical pawn structure, there is no rush to create tension — safe development comes first. Castling also sets a subtle trap: if Black delays castling, White may exploit the open e-file later.

King SafetyDevelopment
Alternative Moves
d3 — Solid but delays king safety. O-O first is more flexible — d3 can come next move.
1
2
3
4
5
6
7
8
h
g
f
e
d
c
b
a
5. ..O-O

Black mirrors again — both kings are now safe. The position remains remarkably symmetrical with all pieces developed identically. The real battle begins with pawn breaks and piece maneuvers.

King Safety
8
7
6
5
4
3
2
1
a
b
c
d
e
f
g
h
View on Analysis Board
6. d3

A modest but important pawn move. White supports the e4 pawn and opens the diagonal for the light-squared bishop while keeping the position flexible. Unlike 6. d4 which would immediately open the center, 6. d3 allows White to choose the right moment to break. The bishop on c1 remains free to develop to g5, e3, or even a3.

Center ControlDevelopment
Alternative Moves
Bxc6 — Exchanging immediately doubles Black's pawns but gives up the bishop pair too early.
1
2
3
4
5
6
7
8
h
g
f
e
d
c
b
a
6. ..d6

Black matches White's setup again — the Symmetrical Variation (ECO C49). Both sides have the same pawn structure: e4/e5 with d3/d6. This is the highest level of symmetry in the Four Knights. The question now is: who breaks the symmetry first, and how?

Center ControlPawn Structure
8
7
6
5
4
3
2
1
a
b
c
d
e
f
g
h
View on Analysis Board
7. Bg5

White breaks the symmetry! The bishop pins the Nf6 to the queen, creating concrete pressure. This is the most popular way to fight for an advantage in the Symmetrical Variation (1,025 master games). The pin forces Black into a strategic decision: trade the bishop for the knight (giving White the bishop pair) or try to maintain the pin with a retreat.

Piece ActivityThreat
Alternative Moves
Ne2 — Flexible but passive. Bg5 creates immediate tension and forces Black to make a concrete decision.
Bxc6 — Trades the active bishop and doubles pawns but loses the bishop pair without gaining the pressure Bg5 creates.
1
2
3
4
5
6
7
8
h
g
f
e
d
c
b
a
View on Analysis Board
7. ..Bxc3

Black trades bishop for knight — the most popular response (872 games). This is a critical strategic exchange: Black gives up the bishop pair but doubles White's c-pawns, creating a lasting structural weakness. The resulting imbalance — White's bishops vs Black's better pawn structure — defines the rest of the game.

Pawn StructurePiece Activity
Alternative Moves
Ne7 — Retreats the knight to break the pin but costs time. Bxc3 is more direct and sound.
8
7
6
5
4
3
2
1
a
b
c
d
e
f
g
h
8. bxc3

Recapturing with the b-pawn toward the center. White accepts doubled c-pawns but gains the half-open b-file and maintains the bishop pair — a classic Nimzo-Indian type trade-off. The doubled pawns on c3/c2 control d4, helping White push d4 later. The bishop pair can become powerful in the middlegame.

Pawn StructurePiece Activity
1
2
3
4
5
6
7
8
h
g
f
e
d
c
b
a
View on Analysis Board
8. ..Qe7

The Metger Unpin — Black slides the queen to e7, breaking the pin on the Nf6 while connecting the rooks. Named after Johannes Metger, this is the main theoretical continuation. The queen on e7 also supports a future ..Nd8-e6 maneuver and keeps an eye on the kingside.

Piece ActivityProphylaxis
Alternative Moves
h6 — Also breaks the pin but weakens the kingside slightly. Qe7 is more flexible.
Bd7 — Develops but doesn't solve the pin. Qe7 addresses the pin and improves coordination.
8
7
6
5
4
3
2
1
a
b
c
d
e
f
g
h
View on Analysis Board
9. Re1

The rook centralizes on the e-file, supporting the e4 pawn and eying Black's queen on e7. If the center opens with d4, the rook will exert pressure down the e-file. This is the most popular master choice (622 of 762 games), preparing the central break while maintaining flexibility.

Piece ActivityDevelopment
Alternative Moves
d4 — The immediate break works but Re1 first improves the rook's position before committing to d4.
Nd2 — Reroutes the knight but blocks the queen. Re1 develops more naturally.
1
2
3
4
5
6
7
8
h
g
f
e
d
c
b
a
9. ..Nd8

A paradoxical retreat — the knight steps back to reroute via e6 or f7, where it can defend the kingside and control key central squares. This maneuver is standard in the Four Knights and shows deep positional understanding. The knight was passive on c6 with the bishop gone from b4; Nd8 begins its journey to a better square.

Piece ActivityProphylaxis
8
7
6
5
4
3
2
1
a
b
c
d
e
f
g
h
View on Analysis Board
10. d4

The central break! With the rook supporting on e1, White pushes d4 to open the position — exactly when the bishop pair can shine in open lines. This is the culmination of White's strategy: patient development followed by a well-timed pawn break. Played in 533 of 541 master games from this position. White's bishops are ready to dominate the resulting open position.

Center ControlSpacePiece Activity
Alternative Moves
Bc1 — Retreats the bishop to avoid exchanges but is overly passive. d4 seizes the initiative.

Key Takeaways

  • Symmetrical development leads to balanced but rich positions
  • Bg5 breaks the symmetry by forcing the bishop-for-knight trade
  • White accepts doubled c-pawns for the bishop pair — a classic imbalance
  • The Metger Unpin (Qe7) is the main way Black breaks the pin
  • d4 is the key central break, timed after Re1 supports the e-file

Summary

You've learned the Four Knights Game — Spanish Variation with the Metger Unpin. White develops symmetrically, then uses Bg5 to provoke ..Bxc3, gaining the bishop pair at the cost of doubled c-pawns. After patient preparation with Re1, the central break d4 opens lines for White's bishops. The resulting positions are rich in strategic play, balancing bishops vs. structure.

Ready to Practice?

Practice InteractivelyAdd to Repertoire

Related Lessons

Halloween Gambit

6 shared moves

Fried Liver Attack

4 shared moves

Giuoco Pianissimo

4 shared moves