Sicilian: Moscow 3...Nd7 4.O-O Nf6 5.Re1 a6 6.Bf1

Sicilian: Moscow 3...Nd7 4.O-O Nf6 5.Re1 a6 6.Bf1

Definition

The line 1.e4 c5 2.Nf3 d6 3.Bb5+ Nd7 4.O-O Nf6 5.Re1 a6 6.Bf1 is a sub-variation of the Moscow (or Rossolimo–Moscow) System against the Sicilian Defence. By checking on move three with 3.Bb5+, White sidesteps many theoretical main lines of the Open Sicilian. Black’s less-common reply 3…Nd7 (the “Novosibirsk Variation”) blocks the check with the knight, after which both sides develop quietly. The retreat 6.Bf1 preserves White’s light-squared bishop and keeps options open for d2–d4 or c2–c3 followed by d2–d4.

Basic move order

The critical moves are:

• 1. e4 c5  – The Sicilian Defence.
• 2. Nf3 d6  – Black signals a possible Najdorf/Dragon setup.
• 3. Bb5+ Nd7  – The Moscow check and Black’s knight block.
• 4. O-O Nf6  – White castles; Black develops, attacking e4.
• 5. Re1 a6  – White defends e4 and prepares c3+d4; Black gains space and questions the bishop.
• 6. Bf1  – The bishop retreats, eyeing c4–e2–h5 diagonals later.

Visualised:

Strategic ideas

• White
  • Supports a later d2–d4 or c2–c3 break while keeping the bishop pair.
  • Can redeploy the Bb5–f1 bishop via g2 after fianchetto or to h3 after Bf1–h3, pressuring e6 and c8.
  • Often aims for quiet, manoeuvring play with c3, d4, a4, h3, Nbd2–f1–g3.
• Black
  • With …Nd7 already played, Black usually develops with …e6 and …Be7, heading for Scheveningen structures.
  • The pawn on a6 discourages Bb5 pin ideas later and prepares …b5 for queenside space.
  • Plans include …g6 and a Maroczy-style bind, or …b5 with thematic …Bb7 and central counterplay with …d5.

Historical context

The Moscow System (3.Bb5+) was popularised in the 1990s by Vladimir Kramnik and Alexei Shirov as an antidote to the Najdorf jungles. The specific 3…Nd7 branch was explored deeply by the Novosibirsk school (Evgeny Sveshnikov and pupils), hence its nickname. While 3…Bd7 has always outnumbered 3…Nd7 at elite level, the “knight-block” line enjoys a solid reputation and appears regularly in rapid and blitz events because it cuts down on theory.

Illustrative games

• Kramnik – Tiviakov, Tilburg 1999
  Kramnik showcased the positional squeeze possible when White’s bishop later emerges on g2.
• Carlsen – Nepomniachtchi, Gashimov Memorial 2019 (blitz) Carlsen used the 6.Bf1 line to keep the position flexible, later steering the game into a favourable minor-piece endgame.

Typical continuations

After 6.Bf1 the main branching points are:

1. 6…e6 7.d4 cxd4 8.Nxd4, entering a Scheveningen-type middlegame.
2. 6…b5 7.a4, when White fixes the queenside and aims at c4 outposts.
3. 6…g6 7.c3 Bg7 8.d4, Black opts for a Dragon-flavoured fianchetto.

Interesting facts & anecdotes

• Because the bishop retreats to f1, some club players jokingly call the line “the boomerang bishop.”
• Garry Kasparov used 3.Bb5+ early in his career but preferred 3…Bd7 lines; still, his analytical team contributed key novelties for 3…Nd7 in the early 2000s.
• Engines rate the position after 6.Bf1 as roughly equal (+0.20 for White at depth 35), making it an attractive practical weapon that dodges Najdorf theory without conceding equality.

When to choose this line

Select 3.Bb5+ Nd7 4.O-O Nf6 5.Re1 a6 6.Bf1 if you:

• want to avoid heavy Najdorf or Dragon preparation;
• prefer slow, manoeuvring play with a small but lasting space edge;
• are comfortable handling hedgehog or Scheveningen pawn structures.