STRATEGY · PIECE ACTIVITY · CALCULATION

A retreat prepares pressure on c5

Korchnoi reroutes his knight before a tactical liquidation. Viktor Korchnoi vs Efim Geller, 1971.

15 minute studyIntermediate26 moves4 moments to think
Efim GellerWhite to move
Viktor KorchnoiStarting position
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Standard starting position. White to move.

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THE STORY BEGINS

Every piece has a part to play.

This short 1971 Candidates quarterfinal game builds its pressure quietly. Korchnoi moves a knight backward, places the bishop on a more active diagonal and adds the queen to the attack on c5. The final capture illustrates why a defended pawn must be assessed against the coordination of every attacking piece.

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22. 23. 24. 25. 26.
GAME BALANCE · WHITE’S PERSPECTIVE+0.37
Accessible evaluation values & provenance

Stockfish 17.1 · 75,000 nodes per position; 1,000,000 at key moments. Actual depth 13–21. Positive centipawns favour White; mate scores remain separate. Selective search is evidence, not proof.

Download complete engine evidence

The story behind the game

This short 1971 Candidates quarterfinal game builds its pressure quietly. Korchnoi moves a knight backward, places the bishop on a more active diagonal and adds the queen to the attack on c5. The final capture illustrates why a defended pawn must be assessed against the coordination of every attacking piece.

Take these ideas to your next game

  1. A backward knight move can prepare a stronger forward route.
  2. Improve a bishop with a concrete target in mind.
  3. Add pressure before resolving a central pawn tension.
  4. After a recapture, inspect the next attacked piece.
Read the complete annotated game

Full game transcript, including the result and the answers. Original explanations by chessgames.info; game score from the sources below.

1 . d4
1 … d5
2 . c4
2 … e6
3 . Nc3
3 … Be7
4 . Nf3
4 … Nf6
5 . Bg5
5 … O-O
6 . e3
6 … h6
7 . Bh4
7 … b6
8 . Be2
8 … Bb7
9 . Bxf6
9 … Bxf6
10 . cxd5
10 … exd5
11 . O-O
11 … Qe7
12 . Qb3
12 … Rd8
13 . Rad1
13 … c5
14 . dxc5
14 … Bxc3
15 . Qxc3
15 … bxc5
16 . Rc1
16 … Nd7
17 . Rc2
17 … Rab8
18 . b3
18 … Qe6
19 . Rd1
19 … Qb6
20 . Ne1

Ne1 prepares a route toward the c5-pawn. The knight’s route matters more than whether its first step goes forward. On d3 it will attack c5 alongside White’s c-file pieces. Black also has active rooks, so the manoeuvre has to be judged against the concrete threats in the position.

20 … Rbc8
21 . Bg4

Bg4 attacks the d7-knight and changes the bishop’s role. The queen steps from b6 to g6, and White’s bishop then moves to h3. From that diagonal the bishop continues to bear on d7. The manoeuvre coordinates with the knight’s route toward d3 instead of seeking an isolated one-move threat.

21 … Qg6
22 . Bh3
22 … Rc7
23 . Nd3

Nd3 adds another attacker to c5. White next brings the queen to a5, keeping pressure on the queenside and centre. Count the attackers and defenders again after Black’s knight moves: changes to one defender can alter whether the rook capture on c5 works.

23 … Nf6
24 . Qa5
24 … Ne8
25 . Rxc5

Rxc5 liquidates the c5-pawn and brings the queen into the centre after the recapture. In the recorded sequence Rxc5 is met by a rook recapture and Qxc5. White’s queen reaches an active central square while the remaining rook keeps contact with the d-file. Compare the resulting position and Black’s alternatives in the saved lines; the resignation is the end of the recorded score, not an additional played variation.

25 … Rxc5
26 . Qxc5

Result: 1-0. The recorded score ends here; it does not imply checkmate.

Think through the turning points

Move 20: Retreat with a destination

Which knight retreat prepares Nd3 to increase pressure on c5? In the game: Ne1. Ne1 prepares a route toward the c5-pawn. The knight’s route matters more than whether its first step goes forward. On d3 it will attack c5 alongside White’s c-file pieces. Black also has active rooks, so the manoeuvre has to be judged against the concrete threats in the position.

Engine-supported alternatives

h3 Rbc8 · +0.25 · depth 18

Ne1 Rbc8 Bg4 Rc7 h3 Nf6 Bf3 Rdc8 Qb2 c4 Rdc1 Ba6 · +0.25 · depth 17

Rdc1 Re8 h3 Rbc8 a4 Ba6 Bxa6 Qxa6 Nh4 · +0.20 · depth 17

Move 21: Make the bishop relevant

Which bishop move attacks the knight on d7? In the game: Bg4. Bg4 attacks the d7-knight and changes the bishop’s role. The queen steps from b6 to g6, and White’s bishop then moves to h3. From that diagonal the bishop continues to bear on d7. The manoeuvre coordinates with the knight’s route toward d3 instead of seeking an isolated one-move threat.

Engine-supported alternatives

Bg4 Rc7 h3 Nf6 Bf3 Rcc8 Qe5 Ne4 Qf5 c4 Qe5 Ng5 · +0.18 · depth 19

h3 Nf8 · +0.10 · depth 19

Bf3 Nf8 Qe5 Ng6 Qg3 c4 Bg4 cxb3 axb3 Rxc2 Nxc2 Qxb3 · +0.09 · depth 18

Move 23: Complete the knight route

Which move brings the e1-knight into contact with the c5-pawn? In the game: Nd3. Nd3 adds another attacker to c5. White next brings the queen to a5, keeping pressure on the queenside and centre. Count the attackers and defenders again after Black’s knight moves: changes to one defender can alter whether the rook capture on c5 works.

Engine-supported alternatives

Nd3 c4 · +0.52 · depth 18

Rcc1 Qb6 b4 c4 Bxd7 Rcxd7 Nc2 Rd6 Nd4 Rg6 Rd2 Re8 · +0.15 · depth 17

Qa1 Qd6 Nd3 d4 exd4 cxd4 Rxc7 Qxc7 Ne1 Nf6 Rxd4 Rxd4 · +0.07 · depth 17

Move 25: Resolve the pressure

Which rook capture removes the pawn on c5? In the game: Rxc5. Rxc5 liquidates the c5-pawn and brings the queen into the centre after the recapture. In the recorded sequence Rxc5 is met by a rook recapture and Qxc5. White’s queen reaches an active central square while the remaining rook keeps contact with the d-file. Compare the resulting position and Black’s alternatives in the saved lines; the resignation is the end of the recorded score, not an additional played variation.

Engine-supported alternatives

Rxc5 Qb6 Qxb6 axb6 Rxc7 Nxc7 Nb4 Kf8 g3 Ke7 Bg2 Ra8 · +2.29 · depth 19

Rcc1 c4 Nf4 Qf6 Ne2 Rb8 bxc4 dxc4 Rd4 Bc8 Bxc8 Rcxc8 · +0.35 · depth 19

Rc3 c4 · +0.15 · depth 19

A CONNECTED IDEA

Improve the piece before changing the position

Korchnoi’s knight retreat prepares d3 and pressure on c5. Compare Karpov’s change of direction and identify the improved piece that makes the next plan possible.

Try it in First one wing, then the other →

Pass the game on.

A good idea is even better shared.

Position images download as SVG. Exact links use saved, validated variations. Unsaved exploration links return to the main-game position.