Four Knights: Scotch, exd4 5.Nxd4 Bc5

Four Knights: Scotch, 4...exd4 5.Nxd4 Bc5

Definition & Move-Order

The Scotch Four Knights is a sub-variation of the Four Knights Opening that arises after the moves:

• 1. e4 e5
• 2. Nf3 Nc6
• 3. Nc3 Nf6
• 4. d4 exd4
• 5. Nxd4 Bc5

By playing 4.d4, White blends the classical Four Knights structure with the central pawn break of the Scotch Game. After the pawn exchange (4…exd4 5.Nxd4) Black’s fifth move …Bc5 targets the d4-knight and f2-square, steering the game into open, tactical channels rather than the modest, often symmetrical lines that can occur in other Four Knights branches.

Strategic Themes

• Central Tension: Both sides contest the central light squares (d4, e5, f4). White’s knight on d4 is advanced but can become a tactical target.
• Piece Activity vs. Structure: Black accepts a small lead in development for White in exchange for rapid piece pressure on c3-knight, d4-knight and f2-point.
• Bishop Pair: The move …Bc5 keeps the dark-squared bishop actively posted; in many lines Black will later play …d6, …0-0 and possibly …Re8 followed by …d5 to free the game.
• King Safety: Tactics against f2 (for White) or f7 (for Black) often appear early. A well-timed 6…Nxe4 sacrifice, or White’s pressure on g7, can tip the balance.

Typical Continuations

White has several respectable sixth moves, each dictating a different middlegame plan:

1. 6.Be3 – Classical main line: 6…Bb6 (retaining the bishop) 7.Qd2 0-0 8.0-0-0 Re8 with a rich, double-edged game.
2. 6.Nb3 – Retreats the d4-knight, eyeing the c5-bishop and the d4-square for a future c3-knight jump.
3. 6.Nxc6 – Liquidates a pair of knights; after 6…bxc6 7.e5 Qe7 White plays for spatial gain but c-structure imbalance offers Black the bishop pair.
4. 6.Nf5 – A sharp sideline hitting g7; Black can reply 6…0-0 7.Bg5 d5! returning the pawn for activity.

Historical Context & Notable Games

The Scotch Four Knights was explored in the late 19^th century when the desire for more combative lines in the otherwise solid Four Knights became popular. Akiba Rubinstein, Emanuel Lasker and later Paul Keres used it to avoid the so-called “Spanish Torture” of the Ruy Lopez. It experienced a revival in the computer-engine era because of its forcing yet relatively unanalysed nature:

• Rubinstein – Tartakower, Warsaw 1926: A textbook demonstration of the 6.Be3 line where Rubinstein’s queenside castling led to a swift pawn storm.
• Carlsen – Aronian, Bilbao 2012: Featured the modern 6.Nb3 variation; Carlsen eventually won a technical queen ending, showing that even symmetrical structures can offer winning chances.

Illustrative Miniature

The following 18-move game underscores the tactical motifs:

Interesting Facts

• Because every move until 5.Nxd4 develops a new piece or occupies the centre, the variation is a favourite recommendation for scholastic players transitioning from gambits to sound openings.
• Engines once assessed 5…Bc5 as slightly inferior to 5…Bb4 (the Belgrade Gambit Denied line), yet modern neural-network engines now give near-equality, sparking renewed grandmaster interest.
• The move order can be used as an anti-Petroff weapon: after 3.Nc3 White avoids 2…Nf6 3.Nxe5 typical of the Petroff because Black’s knight is already on c6.

Practical Tips

• With White, know the traps on f7: 6.Nxc6 bxc6 7.e5 Qe7 8.Qe2 Nd5 9.Ne4 gives annoying pressure.
• With Black, memorize the 9…d5! resource in the 6.Nf5 line to neutralize the pressure on g7.
• Endgame-wise, Black often welcomes exchanges because the symmetrical pawn structure combined with the bishop pair promises equality.