The Left Hook Grand Prix with a3
I have posted further analysis of The Left Hook Grand Prix with a3 (1.e4 c5 2.Nc3 Nc6 3.f4 g6 4.Nf3 Bg7 5.a3), a subject I have written on before. I am surprised that this Left Hook Grand Prix is not covered in any book, especially now that various other Left Hook opening lines have been receiving positive attention (especially the Left Hook Austrian Attack with 1.e4 d6 2.d4 Nf6 3.Nc3 g6 4.f4 Bg7 5.a3!? designed to discourage 5...c5 due to 6.dxc5 Qa5 7.b4 etc., as analyzed in SOS #1, The Carpathian Warrior, Gambiteer I, and The Pirc in Black and White.)
I think of 5.a3 as a high-class waiting move that fits well with any of White's systems, which you can choose based on Black's next move. If Black plays now 5...d6, then White can play 6.Bc4! putting the Bishop on its strongest diagonal, where 5.a3 provides it a nice retreat when the Bishop is attacked by b5 or d5. Play then develops along classic Grand Prix Attack lines, with White typically playing d3, O-O, Qe1-h4 and either f5 or e5 depending on Black's set-up. I like to think of it as the Closed Sicilian with the Bishop on a better diagonal for attack -- and a nice square for the Queen.
If Black plays the more common 5...e6, then White has a nice gambit in 6.b4!? challenging the dark squares. The move is actually more a trap than a gambit, because Black really should not take the pawn: 6...cxb4?! (already a mistake in my view, since it surrenders control over d4) 7.axb4 Nxb4?! 8.Ba3 Nc6 9.Nb5! causes Black no end of grief due to the dark square weaknesses. If then 9...Bxa1? White wins the Queen with 10.Nd6+ Kf8 11.Nxb7+ etc. Best is 9...Bf8 (already a giant concession) 10.Bd6! Bxd6 11.Nxd6+ and White obviously has too much compensation.
As in the French Wing Gambit (discussed last month), Black's best way of meeting 6.b4 is probably by 6...b6! (a move you will likely encounter only from players rated 2000 and above). But White still has play on the dark squares by e5, Ne4, and Bb2 as shown in an illustrative game.
Besides the 6.b4 gambit idea, White also has a good gambit in 6.d4!? which is basically a reversed version of a line in the English known to be quite good for Black. After 6.d4 cxd4 7.Nb5 White either regains his pawn with enhanced central control or gets great compensation with Nd6+ etc.
What I like best about the 5.a3 line is that it continues to be little known to theory despite having been adopted by some high-profile players. So there is a lot of room for improvisation and enterprising play, as the games and analysis demonstrate. It also fits very well with a number of other repertoire suggestions I've been exploring in these pages, including The Caveman Caro-Kann, French Wing Gambit, The Saemisch Surprise vs. the Alekhine, and the Two Knights with d4 for White.