Semi-Slav Defense: Meran Variation

The Meran Variation is one of the main lines of the Semi-Slav Defense: 1.d4 d5 2.c4 c6 3.Nc3 Nf6 4.e3 e6 5.Nf3 Nbd7 6.Bd3 dxc4 7.Bxc4 b5. White's 6.Bd3 provokes 6...dxc4 7.Bxc4 b5, with which Black gives up the centre in exchange for queenside expansion and a tempo against the white bishop. Its ECO codes are D46–D49.

Origins

The line was first played in 1906, in the game Schlechter–Perlis. It takes its name from the town of Meran (Merano) in northern Italy: at a 1924 tournament there it was used successfully in the game Grünfeld–Rubinstein, and two rounds later Grünfeld adopted the same variation against Rudolf Spielmann, winning as well. White plays in the centre, Black on the queenside, and the rich, complicated play that results has long made the Meran a favourite of enterprising players with either colour; an example is Gligoric–Ljubojevic, Belgrade 1979.

The idea

After 7...b5 White has three bishop retreats. The vast majority of games continue 8.Bd3, but 8.Bb3 and 8.Be2 are also possible. On d3 the bishop supports White's plan of pushing e3–e4 and gives the option of Ne4. Black, on the other hand, wants to push ...c6–c5, to free the long diagonal for the light-squared bishop and get rid of the backward pawn on the half-open c-file.

Main lines

• 8.Bd3 a6, the Classical Meran (8...a6), protects the b5-pawn and threatens to equalise with ...c5. White must react in the centre with 9.e4, because 9.O-O allows Black to push the c-pawn freely. After 9...c5:
  • 10.e5 is the classical approach, adopted in several high-level games, including the 2008 World Championship match between Kramnik and Anand. Black continues 10...cxd4, and 11.Nxb5 is the Blumenfeld Variation; 11...Ng4 is the Rabinovich Variation.
  • 10.d5 often transposes to the Reynolds Attack (10.d5).
• 8.Bd3 Bb7, the Modern or Improved Meran (Wade Variation in this database), develops the bishop and keeps the options of ...b4 and ...c5 without spending a move on ...a6. It was long considered virtually unplayable because of 9.e4 b4 10.Na4 c5 11.e5 Nd5 12.Nxc5 Nxc5 13.dxc5 Bxc5 14.Bb5+, until work by Bent Larsen in the late 1960s and early 1970s showed that after 14...Ke7 Black is completely fine.
• 6.Qc2, the Anti-Meran or Stoltz Variation, named after Gösta Stoltz, waits for Black to commit to ...dxc4 before playing Bd3. Once a sideline, it exploded in popularity in the 1990s, in large part due to Anatoly Karpov's advocacy.

Strengths and weaknesses

For Black

• Queenside expansion with gain of time, and active, double-edged play.
• The ...c5 break frees the light-squared bishop.

Against Black

• Black gives up the centre, and the c-pawn is backward until ...c5 is achieved.
• Lines such as the Reynolds Attack are deeply analysed and wildly tactical.

Who should play it

The Meran suits players with either colour who enjoy sharp, theoretical middlegames in which each side plays on a different part of the board.

The numbers

In 324,163 rated Lichess games between players rated 1600 and 2500, Black won 47.9%, White 45.6%, and 6.4% were drawn. Black leads below 2200: 53.9% against 42.8% under 1400 (from only 3,180 games), 51.2% against 44.4% at 1400–1799 and 48.9% against 45.1% at 1800–2199. From 2200 up White is slightly ahead, 46.9% against 45.2%. In about 9,700 master games 51.5% were drawn, White won 26.8% and Black 21.6%.