Magnus Carlsen beats Iranian player MaghSoodloo : Game analysis

Here's the pivotal game, a Berlin Defense where Black increased his advantage gradually.

Ruy Lopez-Spanish Defense

1. e4 e5 2. Nf3 Nc6 3. Bb5 a6 4. Ba4 Nf6 5. d3 b5 6. Bb3 Be7 7. O-O d6 8a4!?

Variation A: Black plays 8..Rb8 to main tension.

 8..Rb8 9. axb5 axb5 10. Nbd2 O-O 11. Re1  

here Black has two options 11..Bd7 which is Carlsen-Topalov 2010 with great attack by Magnus.

The second option is 11..Be6 to fight for control og a2-f7.

11..Be6 12.Bxe6 fxe6 13. c3 Qd7 

here White plays d3-d4 and in King-Krasenkow 1999, White had the edge

 

Variation B: Black plays 8..b4 to prevent any pawn exchange and get space advantage.White typically plays 9.a5!? leading to following position

White typically plays Nbd2-c4 (Bc4 and b2-b3 also possible) and here a possible variation

 9..O-O 10.Re1 Be6 11. Nbd2 Rb8 12. Nc4 Nd7 13. Be3 Bf6 14. c3 bxc3 15. bxc3

De Firmian-Beliavsky game