The Richter-Rauzer is a popular system and is characterized by White playing 6.Bg5 in the Four Knights Position. White will almost always castle queenside in this line, while Black’s king will usually seek safety on the kingside. Surprisingly this system often does not promise direct king assaults. The main focus for both sides tends to be smooth piece development and gaining a fair share of the center.
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Following the moves 1.e4 c5 2.Nf3 Nc6 3.d4 cxd4 4.Nxd4 Nf6 5.Nc3 d6 (or 2…d6 and 5…Nc6), White has just played 6.Bg5. We will now examine one of the less popular lines that guarantees imbalanced play off the beaten path.

6…Nxd4?! 7.Qxd4 helps White to get the queen to a central square. Although this is sometimes played a bit later, we don’t like this move much right now.

6…a6 is a fine move that controls the b5-square, but is often played a bit later in this system. While this is a fine move, we prefer focusing more on the center now.

6…e5?! pushes the d4-knight off the central square with gain of time. On strictly positional terms, this move is dubious however. Now the d5-square is permanently in White’s hands. Play could transpose to a Sveshnikov if White continued with 7.Ndb5. But White could try to exploit the weak d5-square after 7.Nb3 or even 7.Nf5.

6…Bg4? simply loses time after the logical 7.f3.

6…g6?! prepares to develop the dormant f8-bishop to g7. But this is not a good idea at this time as White could give you ugly doubled pawns with 7.Bxf6 exf6. Following 8.Qd2 a6 9.0-0-0 Ne5 10.Kb1, White has to be preferred due to his control over the d5-square.

6…Qa5 pins the knight on c3 and attacks the g5-bishop, but prematurely commits the queen to a mediocre square. White has to be preferred after 7.Bxf6 gxf6 8.Nb3 Qd8 9.Qh5 a6 10.f4. Now look again.

6…e6 is a solid move that allows Black to control the d5-square with a pawn and prepares to develop the f8-bishop to e7 at the right time. Note that the e6-pawn closes the c8-h3 diagonal of the bishop on c8, but it didn’t have any promising options along that diagonal anyways. Black’s main alternative is 6…Qb6, when play usually continues with 7.Nb3 e6. Then 8.Bd3 Be7 9.0-0 and 8.Qd2 a6 9.0-0-0 are two popular lines. Note that 6…a6 is also playable and may transpose later. Black should avoid the committing 6…e5?!, as White could try to exploit the d5-square after 7.Nb3 or even 7.Nf5.

7.Qd2 is the standard setup for White. White sometimes tries the unusual 7.Qd3, but Black has no problems if he continues like in our line. Black should meet 7.Bb5 Bd7 8.Bxc6 bxc6 9.Qf3 with either 9…h6 or 9…Qb6 and reach a fine position.
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The Richter-Rauzer is not as popular on the amateur level as other Sicilian systems such as the Najdorf or the Dragon. This is likely so because the Richter- Rauzer often lacks early tactics and requires positional knowledge.

7…Be7 develops this bishop to its natural post. This is the most popular move at this junction. Play could now lead to two other main lines of the Richter-Rauzer following 8.0-0-0 Nxd4 9.Qxd4 a6 10.f4 0-0 or 8…0-0 9.f4 Nxd4 10.Qxd4 Qa5. Both of these lines require substantial knowledge of current opening theory. Very good, we have chosen a less traveled path that involves delaying development of the dark-squared bishop.

7…a6 is a common move in these types of positions. Besides taking away the b5-square from White’s pieces, Black may also advance the b7-pawn to b5 later on. Black has playable alternatives in 7…Be7, 7…Nxd4, 7…Qb6, 7…Bd7 and even 7…h6. Play after the common 7…Be7 8.0-0-0 could lead to two other main lines of the Richter-Rauzer following 8…Nxd4 9.Qxd4 a6 10.f4 0-0 or 8…0-0 9.f4 Nxd4 10.Qxd4 Qa5. Both of these lines require substantial knowledge of current opening theory.

8.0-0-0 is White’s most consistent continuation and is the best way to play for an advantage. If White castled kingside following 8.Be2 Bd7 9.Rd1 Be7 10.0-0 0-0, play would be more quiet. In Sicilians with an early Bg5, White usually is better off by castling queenside.
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Black needs to keep the center closed as long as his king is there and Black is behind in development.

8…e5? pushes the d4-knight off the central square, but moves the e-pawn again and loses valuable time. On strictly positional terms, this move is dubious. After 9.Nb3 or even 9.Nf5, the d5-square is permanently in White’s hands.

8…Be7 develops this bishop to its natural post. While this is playable, it is not as accurate as on the previous move since Black would not continue with …a6 in that case. Following 9.f4 Bd7 10.Nb3 b5 11.Bxf6 gxf6, White would have a somewhat better version of our line of play. The difference will be the position of the dark-squared bishop on e7 vs. its current position on f8. Leaving it on f8 is often preferable if White ends up taking on f6 a bit later. If Black then recaptured with the g7- pawn, the bishop also has the options of moving to h6 and g7 later on.

8…d5? tries to open the center too early since White is better developed. After 9.exd5 exd5 10.Re1+, Black is facing a tough defense with the king stuck on an open file. Black’s pawn structure is also poor as he would soon get doubled isolated f-pawns as well.

8…Bd7 is a fine developing move that protects the c6-knight and gives Black the option to advance the b7-pawn without losing the c6-knight. In some lines this bishop will later get to the nice c6-square. Note that Black had to play …a7-a6 before moving this bishop to d7 as White could have otherwise played Ndb5 and won the d6-pawn. Black’s main alternative here was 8…h6. Following 9.Be3 Be7 10.f4 Nxd4 11.Bxd4 b5, play would lead down a complicated main line.

9.f4 is White’s most popular reply and gives White the options to continue with f4-f5 or e4-e5 later on, depending on what Black does. Against 9.Be2, Black should avoid 9…b5 and select the solid 9…Be7 10.f4 Rc8 instead. If White selects the more patient 9.f3 instead, Black can proceed with either 9…Be7 or 9…Rc8. 
Following 9.f3 Be7 10.h4, Black can consider stopping White’s kingside ambitions with 10…h5. After 9…Rc8, the game Luther-Kozul (2000) featured 10.Nxc6 Bxc6 11.Kb1 Be7 12.h4 b5 13.Bd3 0-0 14.Ne2 Nd7 with an unclear position. In Solomon-Wolski (2003), White instead continued with 10.h4 Qc7 12.h5 h6 13.Bxf6 gxf6, and Black soon got a fine position by trading queens and bringing his dark-squared f8-bishop to the d8-a5 diagonal.
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In some lines of this system Black will either leave his king in the center or castle on the queenside later on.

9…e5? pushes the d4-knight off the central square, but moves the e-pawn again and loses valuable time. On strictly positional terms, this move is dubious. After 10.Nf5, the d5-square is permanently in White’s hands.

9…Be7 has not done as well as our main line, but is playable. After 10.Nf3 b5 11.Bd3 b4 12.Ne2, White’s position is more promising. Leaving this bishop on f8 for a while is often preferable if White ends up taking on f6 a bit later. If Black then recaptured with the g7-pawn, the bishop also has the options of moving to h6 and g7 later on.

9…h6 is Black’s other good move at this junction. After 10.Bh4, play would be double edged following both 10…Nxe4 11.Qe1 Nf6 12.Nf5 and 10…g5 11.fxg5 Ng4 12.Be2 Nge5 13.Nf3 Be7. While this is a fine idea, we have chosen to seek counter play on the queenside right away.

9…b5 continues with early queenside activity. Black is now threatening to advance the b-pawn to b4 and then capture the unprotected e4-pawn with the f6-knight. Black has several other options, including the popular 9…h6. After 10.Bh4 both 10…Nxe4 11.Qe1 Nf6 12.Nf5 and 10…g5 11.fxg5 Ng4 12.Be2 Nge5 13.Nf3 Be7 are unclear.

10.Bxf6 may seem surprising, but is usually played sooner or later in most Richter-Rauzer systems, especially when Black develops his queenside bishop to d7. After the alternative 10.Nxc6?! Bxc6, Black can meet all 11.Qe1, 11.Qe3 and 11.Bd3 with 11…Be7. Note that the piece sacrifice 10.Bxb5? axb5 11.Ndxb5 is incorrect and should be met with 11…Nb4! 
Note that many club level players continue here with 10.Nxc6 Bxc6 and hope to win the pinned f6-knight with 11.e5?! following 11…dxe5 12.Qxd8+ Rxd8 13.Rxd8+ Kxd8 14.fxe5. But Black then reaches a better endgame following 14…h6, e.g., 15.Bxf6 gxf6 16.exf6 Bd6 or 15.Bh4 g5.
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The leading advocate of this line since the 1980s has been Yugoslav Grandmaster Zdenko Kozul.

10…Qxf6? looks like a reasonable move, but is actually a serious mistake. White could open up the d-file quickly following with 11.e5! Then 11… dxe5 leaves the d7-bishop with insufficient protection. White could take advantage of this by capturing the b5-pawn with the d4-knight. After 12.Ndxb5, White threatens to take the d7-bishop with mate. Following 12…Qd8 13.Nd6+ Bxd6 14.Qxd6, White would have a dominating position. Always make sure your opponent cannot open the center when you are behind in development.

10…gxf6 is the only reasonable recapture since taking with the queen leaves the d7-bishop with insufficient protection. White could open up the d-file quickly following 10…Qxf6? 11.e5! dxe5 12.Ndxb5 and obtain a clear edge due to the mate threat on d7.

11.f5 is a direct means to attack Black’s somewhat compromised pawn structure. Another popular line is 11.Nxc6 Bxc6 12.Qe1, when Black can reach a playable position with 12…Be7 13.Bd3 Qb6 and queenside castling to follow soon. Also 11.Kb1 Qb6 12.Nce2 h5 13.g3 Rc8 leads to a complicated middle game.
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In general Black will try to compensate for his inferior pawn structure and somewhat insecure king position by getting active piece play.

11…e5? pushes the d4-knight off the central square, but permanently loses control of the d5-square. After 12.Nf3, Black’s pieces are passive and his pawn structure is weak and inflexible.

11…exf5? is a very poor move that gives White complete control over the important d5-square following 12.Nxf5 Bxf5 13.exf5. You would also be left with two weak isolated f-pawns and have opened the e-file for a White rook. Better look again.

11…d5?? loses at least a pawn to 12.exd5. Don’t open the center when your king is still stuck there and your opponent is better developed.

11…Nxd4 is a logical move now that White has advanced the f-pawn to f5. Clearly Black has to avoid advancing the e6-pawn to e5 or taking on f5. White would then have complete control over the key d5-square and the win would only be a matter of time. 
Black does have two fine alternatives now in 11…Qb6 and 11…h5. By moving the lady to b6, Black is considering queen trade and also prepares to castle on the queenside. After 12.Nxc6 Qxc6 13.Bd3 Qc5 14.Kb1 0-0-0, play would be unclear. Advancing the h-pawn with 11…h5 instead threatens to win White’s queen with 12…Bh6. White will normally sidestep this by moving the king to b1. Following 12.Kb1, Black continued with the ambitious 12…Ne5 13.Qe1 Qc8 14.g3 Rh6 15.Bh3 Ng4 in the game Zlotnik-Bareev (1992).

12.Qxd4 is a forced move.
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Black has invited White’s queen to a more central square, but the queen no longer controls some other important squares.

12…e5? pushes the queen off the central square, but permanently loses control of the d5-square. After 13.Qf2 and Nd5 to come soon, Black’s pieces are passive and his pawn structure is weak and inflexible.

12…Bh6+ develops this bishop with gain of time on to a long diagonal. This move is the only reasonable continuation after exchanging knights on d4 and takes advantage of the White’s queen moving away from d2.

13.Kb1 is the only reasonable move.
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Play will be quite forcing over the next few moves.

Your move does not give the d6-pawn needed protection and loses material. Better take another look.

Trying to protect the d6-pawn with the queen is futile as White attacks it twice already and could take it anyways with 14.Qxd6. But even better for White is to capture the f6-pawn with 14.Qxf6 instead. You would then lose a piece since both the rook on h8 and the bishop on h6 are left unprotected. Better look again.

13…Bf8?? protects the d6-pawn, but moves this bishop back to the passive square where it just came from. This makes Black’s last move look silly and loses way too much time. Think more active!

13…Ke7?? tries to protect the d6-pawn with the king, but this does not work as White attacks it twice already and could take it anyways with 14.Qxd6+. Better look again.

13…Bf4 is the only reasonable way to protect the d6-pawn. Note how this bishop is now outside the weak pawns on d6 and f6 and can be an active participant in the game.

14.fxe6 tries to open up the position. This capture is becoming necessary soon as Black may soon be able to safely win a pawn on f5. In the game Tal- Kozul (1989), White instead played 14.Ne2 and chased the dark-squared bishop to the nice e5-square. After 14…Be5 15.Qd2, Black won a pawn with 15…exf5 16.exf5 Bxf5 and had fine chances following 17.Nf4 Qb6.
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The soundness of one’s pawn structure often makes the difference between a won and a lost position.

14…Bxe6? loses pawn control over d5 and gives White permanent access to the d5-square for his pieces. Note that Black’s pawn structure would have also been depreciated with isolated pawns on d6, f6, f7 and h7. This cannot be recommended.

14…fxe6 recaptures with the pawn and makes sure Black still controls the vital d5-square. If Black took with the bishop on e6 instead, White would gain permanent access to the d5-square for his pieces. Note that Black’s pawn structure would have also been depreciated with isolated pawns on d6, f6, f7 and h7.

15.Ne2 begins the remaneuvering of this knight. On c3 it would soon be a target. White will now try to get this knight to the better f4-square. If White tries 15.Be2 instead, Black can reach a fine position following the possible move sequence 15…h5 16.Qf2 Be5 17.Rd3 Ke7 18.Rh3 Be8 19.g4 b4 20.Nd1 Bg6.
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Black can be satisfied with the course of the opening.

15…e5?? protects the attacked bishop on f4, but loses the d6- pawn to 16.Qxd6. This is not why we moved the bishop to f4 to begin with.

15…Be5 moves this bishop to its ideal square when it attacks White’s queen, eyes White’s king and also protects the pawns on d6 and f6. Usually White now retreats the queen to d2, but play would be similar against queen moves to d3 or e3. Following 16.Qd2, Black has tried both 16…Qb6 and 16…0-0!? 
The game Hjartasson-Kraut (1995) featured 16…Qb6 17.Nf4 Ke7 18.g3 Rab8 19.Bh3 b4 20.Rhf1 a5 21.Nd3 Qd4, and Black was able to defend successfully.

However, White may be able to improve his attack somewhere. The interesting alternative of kingside castling was played by Kozul himself in 1994 in his game against Tolnai. Following 16…0-0 17.Nd4 f5 18.Nf3 Bc6 19.Nxe5 dxe5 20.Qe1 Qc7, Black was already slightly better. It is difficult to improve White’s play in this line as 18.exf5 exf5 gives Black isolated pawns on d6 and f5, but Black’s strong pieces more than compensate for this after e.g., 19.Nf3 Bc6 or 19.Be2 Qf6. 
It appears as if the line with 11.f5 does not promise White reasonable chances for an edge. In fact, he has to be careful that Black’s bishop pair doesn’t take over the game quickly.

The final position is quite telling. White’s f1-bishop is still on the back rank and doesn’t have a bright future, whereas Black got rid of his doubled f-pawns and also has a very strong bishop on e5. White will usually try to exchange his knight for the e5-bishop, but even that did not cause Black much trouble in the above two games. We believe that White is better off playing the more patient systems starting with 11.Kb1 or 11.Nxc6. Black has no reason to shun this line, but if you desire to look at other options we recommend looking at the systems originating from 8…h6 and 9…h6.