sicilian defense najdorf

Recetly I have been facing the sicilian najdorf in the tornaments and the moves always go like this...1.e4 c5 2. nf3 d6 3. d4 cxd4 4. nxd4 nf6

5.nc3 e6 6.Bc4 a6.

I was wondering why after move 6, a4 is not given to prevent b5.

It seems that a4 is a good move to me as it stops b5 and prevents a quick queenside attack. What is your opinion on this ?? Thanks for the help in advance.

It's a playable move, but the move b7-b5 also leaves Black tactically weak on the h1-a8 diagonal which can be exploited by White playing Qf3 soon i.e. 7.O-O b5 8.Bb3 Be7 9.Qf3, while an early Bb7 is well-met by sacrifices on e6 i.e. 7.O-O b5 8.Bb3 Bb7?! 9.Bxe6 (I think 9.Re1 is also good).

But does this move have any weaknesses for white, or does it only have plus points for white ?

It doesn't develop a piece, and it allows Black to set up a more solid defensive structure. Also Black can.more safely go for a hedgehog structure.

I hate when people post the first 7 moves of an opening, of course its playable you should have been able to come to that conclusion yourself by looking in any of the databases on the internet.

He's asking for the reasoning and pros and cons of a 6th move that is not the most common move. How are you going to get this information from a database? I don't see any reason for you to be hating on his thread.

Mainline moves for black are 5 ...a6 and move 6 ...e6, but it looks like your opponents are playing e6 before a6?

Well, 7.O-O b5 8.Bb3 b4?! 9.Na4 Nxe4? 10.Re1 is already close to winning for White, and 9...Bd7 10.c3 already solves the problem of the off-side Knight. Clearly Black can't keep a pawn on b4 in the long run because he has a 'pawn minority' on that side of the board, so White has two ways to attack the pawn with another pawn and Black only has one way to defend it with a pawn.10...a5 11.Be3 also eyes the b6 square, a nice place for the Knight from a4 to go!

Well, put like that, it seems that the sicilian is quite easy to beat. Thanks for your help, Expertise87. Your advices have helped me unerstand the way to kill the najdorf ( like fischer killed the dragon).

But after 10)Re1, how is it winning  for white when black can easiliy play d5 ??

Please don't get the wrong idea. Black has already made two errors to get to the position I called 'close to losing.' The Sicilian mainlines are certainly easier to play for White than Black, who can be losing after even a small error, while White has much more leeway.

10.Re1 d5 11.Bf4! activates all of White's pieces effectively and Black is actually powerless to defend against the many positional and tactical threats. Some key ideas include opening the c-file and putting a Rook on c1, sacrificing a Knight on f5 (i.e. 11...Be7 12.Nf5! exf5 13.Qxd5 threatening f7 and a8 13...Qxd5 14.Bxd5 where the Rook on a8 is hanging and 14...Ra7 drops the b8-Knight), etc. Basically in a position like this when the e-file is available for White and Black's king is stuck in the center, Black is basically toast.

Actually, Houdini 3 evaluates the position as clearly better and almost winning for White after 11.Bf4, which I was a bit surprised by. I know that in practice Black is lost, but a computer coming to the same conclusion when Black is already up material is surprising. The computer's choice for Black is 11...Nf6 where 12.Rc1 planning c2-c4 creates unsurmountable problems for Black.

Why do you.have White retreating to d3 and not b3?

Estragon wrote:

7 a4 Be7  8 0-0 0-0  9 Be3 Nc6 is a known line, roughly even, Black is okay.

Also after 7 0-0 b5 8 Bd3 Bb7 Black has a reasonable game.

More usual is 7 Bb3 b5  8 0-0 Be7  9 Qf3, but Black again gets decent results.

The problem here is White's 6 Bc4, which makes much less sense against a Nadjorf or Scheveningen move order than when Black plays an early ...Nc6.   This is why 6 Be2 or 6 Bg5 are White's more common choices.

What about 6.a4 followed by g3 and Bg2? For example: 6.a4 e6 7.g3 Be7 8. Bg2. Still legit?

Yes.