Chess Opening Theory/1. e4/1...e5/2. Nf3/2...Nc6/3. Bb5/3...a6/4. Ba4/4...Nf6/5. O-O/5...Nxe4/6. d4/6...b5/7. Bb3/7...d5/8. dxe5/8...Be6/9. Nbd2

Bernstein variation C80 Spanish game → Open Spanish → 8...Be6 9. Nbd2 · Bernstein variation White develops their knight to d2. This is the main alternative to 9. c3. After 9. c3, White can meet 9...Nc5 with 10 Bc2 and keep the bishop pair. Instead, 9. Nbd2 is an offer to trade bishop for knight. White allows 9...Nc5 10. c3 Nxb3!? as they can recapture 11. Nxb3 and avoid doubling their pawns. However, on d2, White's knight obstructs the development of their bishop, so if Black doesn't take on b3, White will have to spend time untangling their position. Most common today is 9...Nc5 10. c3 Be7 (Black does not wish to trade and help White to improve their knight) 11. Bc2 (intending 12. Nb3), and the game might continue 11...d4 12. Nb3 dxc3 13. Nxc5 Bxc5 14. Be4 (attacking c6, which is pinned to a8) Qd7+.e.g. Nakamura v Carlsen, 2021. Chessgames.com 10...d4 is an alternative. ...d4, before White has had chance to play Bc2, offers to trade the light-square bishops: The old line goes 11. cxd4 Nxd4 12. Nxd4 Qxd4 13. Bxe6 Nxe6 14. Qf3 Rd8.as played in Capablanca v Lasker, 1914. Chessgames.com More common nowadays is 11. Bxe6 Nxe6 12. cxd4 Ncxd4 for an even game. 11. Ng5!?, the Karpov gambit, was introduced in the World Championship Match in 1978. One idea behind the knight sacrifice is to allow White's queen to come to f3 and increase pressure on Black's weak long diagonal, 11...Qxg5 12. Qf3 Kd7?! (an attempt to defend the knight on c6) 13. Bd5!++. 12...Bd7 to defend the knight allows 13. Bxf7+!. The best move for Black is 12...O-O-O 13. Bxe6+ fxe6 14. Qxc6 Qxe5, allowing White to recover the knight.In Kasparov v Shirov, 2001 (Chessgames.com) the game continued 15. b4 Qd5 16. Qxd5 exd5 17. bxc5 dxc3 18. Nb3 d4. White is up a knight for two pawns but Black has full compensation. 9...Be7 is the main side line: seeing that hunting down the bishop is now less appetising, Black would simply like to castle and play f5. White still would like to play the c3, Bc2, Nb3 manoeuvre to straighten out their queenside. If 9...Bc5, which increases pressure on f2 and is the main move after 9. c3, White can trade off the knight 10. Nxe4 dxe4 11. Ng5 (not a gambit this time!) Qxd1 12. Rxd1 Bxb3 13. axb3+. History Ossip Bernstein played this line against Siegbert Tarrasch in 1914.Bernstein v Tarrasch, 1914. Chessgames.com Theory table 9...Nc5 10. c3 Be7 11. Bc2 d4 12. Nb3 dxc3 13. Nxc5 Bxc5 14. Be4 Qd7 + Bernstein variation 9. ... ... 10. ... d4 11. Bxe6 Nxe6 12. cxd4 Ncxd4 9. ... ... 10. ... ... 11. Ng5!? O-O-O 13. Bxe6+ fxe6 14. Qxc6 Qxe5 Karpov gambit 9. ... Be7 10. c3 O-O 11. Bc2 f5 12. Nb3 Qd7 + 9. ... Bc5 10. Nxe4 dxe4 11. Ng5 Qxd1 12. Rxd1 Bxb3 13. axb3 + References See also