Catalan opening in Carlsen vs Karjakin, St Louis 2018, answering student's question

Q: Black has just played 8......Nc6 giving himself temporarily a tripled c pawn in return for the exchange of White's Bishop on g2. This move looks very anti-positional.The previous Black move 7....dxc4 looks bad for Black as well as 8.....Nc6.

Could you please comment about these two strange Black moves.

A:That's a nice question! Yes, these moves by Black do look weird at first glance. But they also have positional background, even that executed in a very dynamic way. First we can have a look at the capture dxc4. This is the case when Black is already developed rather well, casled etc, and now he can consider this capture, because it opens the file D to his Queen, which already makes a direct pressure on centre and keeps d4 at sight. Then Black usually hopes to do something like c5 in these schemes, with even more pressure there. And Nc6 has a similar idea - a clear one - to put more pressure on centre, and also the file b opens after the exchange, and Rook can take it someday; and one more important point - Black gets a chance to sac the extra pawn he has now back but to obtain activity and dynamic in exchange. In this case this can be an exchange of one of the most active White pieces - either Bishop g2 or Knight e5. And if White accepts it, then his position instead of a typical solid Catalan-like positions can go in another direction. And for the tripled pawns he has a compensation like open b and d files with views of pressure on important pawns there, and White can get busy defending those and can lose in general mobility of pieces and simply have no time to hunt for the tripled pawns comfortably.

Answering a student's question

Q:
Could I ask you about this position (Danis v Skora Corr 1977)?

In this variation of Black's 21-st move, White has just played 25. g3! Why has the annotator has given this an exclamation mark? What is the idea behind this move( if 25.Kc7 then 26.h4 h6 and still W cannot get control of f4 for his Queen)?This plan is slow and will fail for White.

A:

Here it just looks like some missplelling or a typo. I guess that the move was Qg3!!  there,  with irrefutable kingatack, and not g3. Also White is a piece down here, and g3 is just useless there, it looks like he had sacrificed a piece previously somewhere in order to obtain this opportunity of King-attack with Qg3. A nice position and example, indeed☺

Answering student's question on French Defense

The French Defense Question:

If the opening goes :

1. e4 e6 2. d4 d5  3 Nc3 Nf6  4. e5 Nfd7  5 Qh5 c5  6.Nf3 ( with  the threat of the dangerous 7. Ng5 )

How does Black refute White's premature  5 Qh5?


The answer:

Against the 1. e4 e6 2. d4 d5 3. Nc3 Nf6 4. e5 Nfd7

5. Qh5 c5 6. Nf3 it can be simply g6, and now White fails to coordinate his Queen and Knight in time to attack f7. 

7. Qg4 cxd4 8. Nxd4 Nxe5

9. Qg3 Bg7 g6 is also a place for the Bishop to be fianchetted and make pressure on centre. 

10. Bf4 Nbc6 11. Nxc6 Nxc6 12. for example Bd6, to try to delay the castle;  a6

13. O-O-O Ne7 theratening Nf5 and at the same time insisting in castle. 14. Ba3 O-O 15. h4 h5 16. Ne4 Nf5

17. Qh2 Qb6 18. Bxf8 Bxb2+ 19. Kd2 dxe4 with winning position for Black.