1. e2e4  1... e7e5  2. g1f3  2... b8c6  3. f1b5  3... a7a6  4. b5a4  4... g8f6  5. e1g1  5... f6e4  6. d2d4  6... b7b5  7. a4b3  7... d7d5 The Open Ruy Lopez has been the favorite weapon of Korchnoi and Mamedyarov, but many other top players have also given it a try lately. 8. d4e5  8... c8e6  9. b1d2  9... f8e7  10. c2c3  10... e8g8  11. b3c2  11... f7f5  12. d2b3  12... d8d7  13. f3d4 This can be named the key square in the Open Ruy Lopez. 13... c6d4  14. b3d4 