Kammala jumla mai zuwa: Karpov yayi kokarin 9...Nd7 sau da yawa a cikin
1990 Gasar cin Kofin Duniya, amma Kasparov ya sami fa'ida mai yawa a kanta a wasa na 18. Yana da ƙarfi amma dan kadan m. Rashin rikicewa 9...Nd7 kuma ana kiranta da bambancin Chigorin don haka akwai bambance-bambancen biyu na Ruy Lopez tare da wannan sunan, amma 9...Na5 shine motsi mafi yawanci da aka danganta da Chigorin. Wannan tsaron kuma an san shi da bambancin Keres, bayan Paul Keres.