1. e2e4  1... e7e5  2. g1f3  2... b8c6  3. f1b5  3... a7a6  4. b5a4  4... g8f6  5. e1g1  5... f6e4 The Open Variation is one of Black's best choices in the Ruy Lopez. 6. d2d4  6... b7b5  7. a4b3  7... d7d5  8. d4e5  8... c8e6  9. c2c3  9... f8e7  10. b3c2 Only the fourth most popular move and much rarer than the main line 10.Nbd2.