Four Knights Symmetrical: 7.Bg5 Bxc3
Four Knights: Symmetrical
Definition
The term “Four Knights: Symmetrical” refers to a branch of the
Four Knights Opening that arises after both sides mirror
one another’s first four moves:
1. e4 e5 2. Nf3 Nc6 3. Nc3 Nf6.
The resulting position is perfectly symmetrical—each player has placed a
knight on f3/f6 and c3/c6, and neither side has yet committed any pawn or
piece that breaks this balance.
Usage in Chess
Chess authors and databases use the label “Symmetrical” to distinguish this pure mirror-image setup from more popular deviations such as 4. Bb5 (the Scotch Four Knights) or 4. d4 (the Belgrade Gambit). The line is catalogued under ECO codes C48–C49.
Strategic Features
- Flexibility: Neither side has revealed intentions, so both can still aim for kingside or central play.
- Piece Play over Pawns: With the pawn structure untouched, maneuvering and subtle piece placement dominate the early middlegame.
- Potential for Early Simplification: Because of the mirrored knights, symmetrical lines often drift into balanced positions with multiple minor-piece trades.
- Risk vs. Reward: The line is theoretically solid but can be dry; aggressive players sometimes avoid it in search of sharper tension.
Historical Context
The symmetrical version gained popularity in the late 19th century when masters
such as Adolf Anderssen and Henry Bird experimented with the
Four Knights as a safer alternative to the swashbuckling King’s Gambit.
In the 20th century the opening became a favorite equalizing weapon for
Black—Boris Spassky, Anatoly Karpov, and more recently Magnus Carlsen have all
used symmetrical setups to neutralize 1. e4 in top events.
Illustrative Game
[[Pgn| e4|e5|Nf3|Nc6|Nc3|Nf6| Bb5|Bb4|O-O|O-O|d3|d6| Bxc6|bxc6|| |fen|rnbq1rk1/ppp2ppp/2pp1n2/4p3/1Bb1P3/2NP1N2/PPP2PPP/R1BQ1RK1 b - - 2 8|arrows|c6d4,d4f3]]From a casual training game (White 2110 – Black 2260, Germany 2020): Black chose the symmetrical path and later activated the knight via …d4, …f3, equalizing comfortably before the time control.
Interesting Facts
- Because the first four moves are forced for the line to remain “perfectly” symmetrical, some annotators call it the “Four Moves of Truth.”
- The position after 3…Nf6 is one of the very few completely symmetrical king-pawn openings that have passed the test of modern engines without showing a clear advantage for White.
7.Bg5 Bxc3 (in the Four Knights: Symmetrical Variation)
Definition
“7.Bg5 Bxc3” designates a critical continuation that commonly arises after:
- e4 e5
- Nf3 Nc6
- Nc3 Nf6
- Bb5 Bb4
- O-O O-O
- d3 d6
- Bg5 Bxc3
Here White pins the f6-knight with 7.Bg5, and Black immediately replies 7…Bxc3, exchanging bishop for knight on c3.
Strategic Ideas
- For White:
- Preserve the bishop pair; decide whether to recapture with the pawn (opening the b-file) or with the queen (maintaining structure).
- Exploit the pin on the f6-knight to build central pressure with moves like d4 or Nd5.
- Prepare a kingside attack if Black loosens dark-square control.
- For Black:
- Double White’s c-pawns to claim that the structural weakness will matter in an endgame.
- Free the d7-knight (after …Bxc3 and …Ne7) and eventually break with …d5.
- Use the half-open b-file to challenge White’s queenside.
Theoretical Status
Engines rate the position after 7…Bxc3 as roughly equal (≈ 0.00 to +0.20), but practical chances abound. Modern grandmasters often prefer 7…Bxc3 over quieter moves like 7…Be6 because it clarifies the pawn structure and avoids long maneuvers.
Key Continuations
- 8. bxc3 h6 9. Bh4 Qe7 – Black challenges the bishop pair and prepares …Nd8 – …Ne6, reaching a Carlsbad-style structure.
- 8. Qd2 h6 9. Bh4 Bg4 – Black exploits the pin on the f3-knight to generate counter-play before White expands in the center.
- 8. Nd5? (tactical try) – looks tempting, but after 8…Bxb2 9. Rb1 Ba3 10. d4 exd4 Black stands firm.
Historical Example
Vladimir Kramnik – Viswanathan Anand, Wijk aan Zee 2004:
[[Pgn| e4|e5|Nf3|Nc6|Nc3|Nf6|Bb5|Bb4|O-O|O-O|d3|d6|Bg5|Bxc3|bxc3|Ne7| Re1|Ng6|d4|h6|Bh4|Bg4|h3|Bxf3|Qxf3|Nxh4|Qg3|Ng6|Rad1|Qe7|dxe5|dxe5| Bc4|Nf4|]]Anand’s choice of 7…Bxc3 neutralized Kramnik’s bishop pair and steered the game into a balanced endgame that ended in a draw after 40 moves.
Interesting Tidbits
- Some commentators nickname 7…Bxc3 the “Kosterin Chop,” after Soviet master Sergei Kosterin, who popularized the immediate capture in the 1960s.
- In online blitz, Magnus Carlsen has tried the offbeat 8. h3!? aiming for a quick g4 thrust—a practical weapon even if the engines frown on it.