1. d2d4  1... g8f6  2. c2c4  2... e7e6  3. g2g3  3... d7d5  4. f1g2  4... d5c4  5. g1f3  5... f8b4  6. c1d2  6... a7a5 Topalov had used this line as a main anti-Catalan weapon in two WCC matches, against Kramnik and Anand. 7. a2a3  7... b4d2  8. b1d2  8... b7b5  9. b2b3 A topical line. White gains full compensation for the pawn, but Black can be quite satisfied with the opening outcome as he manages to trade a bunch of pawns on the queenside. 9... c4b3  10. d1b3  10... c7c6  11. e1g1  11... e8g8  12. b3b2  12... b8d7  13. f1c1 The half-open b- and c- files are White's main compensation. Gukesh needs to fix the weakness of the c5-square as soon as he can.