1.a3 Nf6 2.e3 e5 3.c4
This position obviously can also arise from the move-orders 1.c4 e5 2.e3 Nf6 3.a3 or 1.e3 e5 2.c4 Nf6 3.a3.3...d5!?
This enters an Open Sicilian position a move down and looks a bit too optimistic. However, the normal result of a correctly played Open Sicilian is a small advantage to White. It could well be that losing a tempo only leads to equality - which is an excellent result for Black.4.cxd5 Nxd5 (Dia)
Now we have a Reversed Kan Sicilian on the board. With reversed openings it can sometimes be hard to say whether White has an extra move or Black has one less. But in this case it’s quite clear: White has got a free move. How can he best use it?5.Nf3!?
a) I am confident that if this variation should ever become popular, 5.b4 would be one of the first moves to receive serious attention. So far I could find no practical examples.b) 5.Qc2 is the main line in the comparable reversed position but could be too quiet to achieve anything against modest development by Black:
b1) 5...Bd6 6.Bd3 Qg5 7.Ne2 c6 8.Ng3 Bc7 9.0–0 Nd7 10.Nc3 N7f6 11.Nxd5 Nxd5 12.b4 h5 13.Bb2 Bh3 14.gxh3 h4 15.Be4 (15.Ba6) 15...hxg3 16.Bxd5 and White was clearly better in Rodriguez Lopez-Castillo Martinez, Mislata 2000.b2) 5...Nc6 6.Nf3 a6 7.Nc3 Be7 8.Be2 0–0 9.h4 h6 10.b4 Be6 11.Bb2 Nxc3 12.Bxc3 Bf6 =+ Sattari-Cheparinov, Dos Hermanas Internet Blitz 2004.
5...Bd6a) 5...Nc6 6.Nc3 (6.Bb5) 6...Be6 7.Qc2 a6 8.Be2 Be7 9.0–0 Qd7 10.b4 0–0 11.Bb2 Bf6 12.Na4 Qe8 13.b5 axb5 14.Bxb5 Bd7 (14...e4) 15.Nc5 Ncb4 16.axb4 Bxb5 17.Rxa8 Qxa8 18.Ra1 += W.Paulsen-Flechsig,
b) 5...Nd7 6.Qc2 c6 7.Nc3 N5f6 8.Bc4 Bd6 9.b4 0–0 10.Bb2 Qe7 11.Ng5 Nb6 12.Ba2 g6 13.h4 Bf5 14.Nce4 Nxe4 15.Nxe4 Rad8 16.h5 Nd7 17.g4 Bxg4 18.hxg6 hxg6 19.Nc5 with a clear advantage to White in
This is the normal Kan move but doesn't appear very threatening and may allow Black to reach an acceptable position with modest play. However, if Black plays modestly White's long-term advantages - in particular his central majority - may become an important factor. Alternatives include:
a) By parallel from the reversed lines, 6.Bc4 Nb6 7.Ba2 should be an important line.b) 6.d3 Nc6 7.b4 a6 8.Bb2 Be6 9.Nbd2 0–0 10.Nc4 f6 11.Be2 Re8 12.0–0 Bf8 13.Rc1 Qd7 14.Qc2 Rad8 15.Rfe1 = Kunte-Suvrajit, Atul 2006.
c) 6.Nc3 Nxc3 7.bxc3 (7.dxc3 0–0 8.e4 a5 9.Bc4 a4 10.0–0 Bg4 11.h3 Bd7 12.Bg5 += Eichler-Baumgartner, Austria 2000) 7...0–0 8.d4 exd4 9.cxd4 c5 10.d5 Nd7 11.Bb2 Nf6 12.Bc4 a6 13.a4 Bf5 14.0–0 Rb8 15.a5 += Steinitz-Rosenthal, Vienna 1873.d) 6.e4 Nb6 7.d4 exd4 8.Qxd4 0–0 9.Bd3 Nc6 10.Qc3 Re8 11.Bg5 f6 12.Be3 Ne5 =+ Symeonidis-Panagiotopoulos, Nikea 2004.
6...0–0 7.b4White has also tried:
a) 7.d3 Re8 8.Nbd2 Bf8 9.Be2 a5 10.b3 a4 11.b4 c5 12.bxc5 Na6 13.Bb2 was very good for White in
b) 7.Bc4 Be6 (7...Nb6 8.Ba2 Qe7 9.h4 N8d7 10.Ng5 Nf6 11.Nc3 Kh8 12.Ne2 e4 13.f3 Nbd7 14.fxe4 c5 15.d4 gave White the advantage in Bosboom-Ellenbroek, Enschede 1993) 8.Qb3 c6 9.Nc3 Nd7 10.d4 Rb8 11.e4 Nxc3 12.bxc3 Bg4 13.Be2 c5 14.d5 b5 =+ Pantsulaia-Dzagnidze, Istanbul 2006.7...Nd7
Or 7...Bg4 8.Bb2 Nd7 9.Be2 Kh8 10.d3 f5 11.Nbd2 Qe7 12.h3 Bxf3 13.Bxf3 N7f6 = Bouhallel-Marchadour, Avoine 2006.8.Bb2 Re8 9.Bc4 N7f6 10.d3 c6 11.Nbd2 Bg4 12.Ng5 h6 13.Nge4 Bf8 14.h3 Bh5 (Dia)
So far the play has looked rather calm and positional. Now White decides to use his active pieces, his central majority and his delayed castling in a kingside attack.
15.g4 Bg6 16.Rg1 Nxe4 17.dxe4 Qh4 18.Rg3 Rad8 19.Nf3 Qf6 20.h4
It's becoming clear that White's attack is very dangerous.
This fails for tactical reasons - the pin in the b1-h7 diagonal can be neutralized. After 20...Nb6 White's attack still seems promising but nothing is really decided.21.h5 Bh7 22.g5 b5
Now 22...Nb6 is met decisively by 23.g6.23.Bb3 hxg5 24.Nxg5 Be7 25.Nxh7 Nb6 26.Rg6 Qd3 27.Bxe5 Bxb4+ 28.axb4 Rxe5 29.Qb2 Kxh7 30.Qxe5 fxg6 31.hxg6+ Kh6 32.Rd1 Qxb3 33.Rxd8 Qxb4+ 34.Kf1 1–0 Kjartansson-Baldursson, Reykjavik 2006.