It is surely true that ...cd isn't something Black should be eager to do.  For example it isn't the normal reply to 9. b3 (in the regular Tarrasch move order), which could lead one to wonder if 10. b3 in the move order under discussion isn't indeed good for White.

I was surprised when I saw a 2100 player play an early ...cd against Avrukh a few months ago; the follow-up there reminded me of the classic Rubinstein-Salwe game.

Just think of this. What is better for Black: to have the pawn on h6 or not? For sure having the pawn on h6 is an improvement for several reasons (no back rank mates, control of g5 square while there is no obvious drawback such as weakening of the g6 square which is not relevant at all). So, and only by this simple comparison, you can understand why you should prefer Be3 over Bg5 if Black exchanges on d4 soon.

A more subtle explanation is that the move 9.Bg5 in the main line Tarrasch forces Black to make a concession because the d5 pawn is in danger. So Black has to play Be6 (blocking the 'e' file, putting the Bishop on an exposed square etc), play c4 (which takes away the tension of the centre allowing K-side attaks based on f4 or play positionally with the b2-b3 break) or cxd4 (which gives the Nd4 square to the Knight, opens the Bg2 and clarifies the situation at the centre and so on...). So, Bg5 forces an concession, which means to give you something! There is no need to play this move if Black has already given you that something!

Sorry, this has nothing to do with the book, but is a general Tarrasch question - I thought best to include here.

I have had two players play ..cxd4 quite early before I've played Bg5 in the main line.
Eg: 1.d4 d5 2.c4 e6 3.Nc3 c5 4.cxd5 exd5 5.Nf3 Nc6 6.g3 cxd4

I couldn't think of anything clever enough other than transposing to main line with a later 7.Nxd4 Nf6 8.Bg2 Be7 9.0-0 0-0 10.Bg5 which is what i played.

Searching for options I see that 10.Be3 is more often preferred without inducing ..h6. (In the main line ..cxd4 occurs after Bg5). 
So what's the difference if cxd4 has already occured? It's a bit too subtle for me. 
Is it to do with the c5 square?

I assumed taking on d4 early must be a bit of a mistake on blacks part - but I can't find anything dramatic for white.

Thanks for the comments. What I do is type up the the opening Tabiyas to move 8 and probably a few (2 or 3) early deviations. I study the opening by playing over games from there. Theory very light.

My summary of Marin's book on the Open Game in less than 2 pages. I love that book.
What concerned me a little was the position following 5. dc5,d4.  The kind of move people play against me. I have gone over the position and am comfortable with it - I think I can solve over the board.

Playslikefish wrote on 02/26/11 at 15:58:31:


In conjunction with the Marshall article, also have a good look at Kasparov's games in this variation, since he brought the Tarrasch to relative respectability in the 1980s. Karpov gave him a bit of a beating in their 1984/85 match, true, but Black has found improvements over these games, and you will not be playing a Karpov. 

On another note, if you're a bit of a gambiteer you can wheel out the Von-Hennig Gambit (3.Nc3 c5 4.cd5 cd4) occasionally for a bit of fun. 5.Qa4 Bd7 6.Qd4 ed5 7.Qd5 Nf6 8.Qd1 Nc6 9.Nf3 Bc5 10.e3 Qe7 11.Be2 0-0!? is the critical line for both sides.

The theory-heaviness of the Tarrasch (however it may rank versus other major openings) is about the last thing you should be worrying about.

The bad thing about 9...cxd4 is the many good options available to White.

9...Be6 is indeed the "old mainline" and the move that was played by Keres all the time. I don't think that the Avrukh proposed ending (Petrosian's forced line) is bad for Black. Jacob thinks otherwise and he is probably right but i am still not convinced and i have a specific recommendation against it. Also the Khalifman's proposal can be met by a neat way. 10.Rc1 is not critical at all though. Black just plays 10...c4! and he reaches a "safe" 9...c4 variation by transposition of moves.

9...c4 is a move that seems incorrect at first sight but it is actually simpler to play than 9...cxd4 and the play is "slower" and can be called more positional. We examine the "traditional" ways than Black has used till now against various attempts by White to gain an advantage but the real revelation of the book is the examination of a a new concept, a new way that Black can play and challenges directly the White's advantage. After so many months of analysis , gathering of the material and multiple tries of refutation we still didn't manage to prove Black's concept wrong.

That's why our main line in the book is 9...c4!

I think that after 9...cxd4 10.Nxd4 h6 11.Be3 Bg4 White is slightly better in both BPaulsen's lines and in Buecker's 14.Qb3 which made me stop looking the line for Black. Unfortunately 11...Re8 12.Rc1 Bg4 is no easy for Black either. Just look at Ward's proposal from his QGD book for example. More simple than the line given by Sokolov and Khalifman which is still better for White. As for the Kramnik's line with 13.Na4, again White seems to have an edge here although in club play i wouldn't mind be Black. The problem with 11...Re8 is that there are a number of dangerous possibilities that are also theoritically dangerous such as 12.Qa4 for example which was Cox's proposal and has been covered in other sources as well such as NIC Yearbooks.

BUT! In my opinion 9...Be6 is playable and fully sound. It will not be covered in the book, that's why my research on it is not complete yet, but from what i have seen i consider it at least a better practical try from 9...cxd4.