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Practice: St. Petersburg Variation

Main line with O-O and c5

The main line of the St. Petersburg Variation. Black plays ...O-O and ...c5 to challenge White's centre, with the bishop pair as a long-term asset.

1. d4 Nf6
2. c4 e6
3. Nc3 Bb4
4. e3 b6
♟

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Key strategic ideas

  • Black pins the knight on c3 with ...Bb4, stopping White from playing e4 and building the ideal centre.
  • White can force the trade (a3, then Bxc3, doubling the c-pawns but getting the bishop pair) or avoid it (Qc2, keeping the knight but allowing Black to put pressure on the queenside).
  • The Rubinstein Variation (4.e3) is the solid choice. White develops simply and recaptures on c3 with the d-pawn, keeping the centre strong.

Common mistakes & traps

  • After 4.Qc2 d5 5.a3 Bxc3+ 6.Qxc3, Black can play 6...Ne4! attacking the queen and forcing it to retreat. This gains a free tempo for central expansion.
  • The Leningrad Variation (4.Bg5 h6 5.Bh4 c5 6.d5 d6) is very sharp. If Black pushes ...b5 too early, White can strike with Bxf6 and Qd2.

Pawn structure notes

If Bxc3 is played, White gets doubled c-pawns but the two bishops and a solid centre (d4-e3). Black has more pawns on the queenside and can create a passed pawn in many endgames.

Tips

  • The St. Petersburg variation focuses on a quick ...b6 and ...Bb7
  • Develop the bishop to b7 before committing the king's position
  • The ...c5 break challenges White's centre and opens lines for your bishops
  • Be flexible with the knight on f6 — it can redeploy to e4 or d7
  • Watch for White's a3 followed by axb4 if the bishop stays on b4

About this line

This line is rated intermediate. Practice it repeatedly until you can play the entire sequence without thinking. The in-app trainer tracks your perfect streaks and celebrates milestones.