10-15 21-17

10-15, called Kelso, is towards the center, but from the double corner. It is considered Black's fourth strongest opening. (Some experts say it is as strong as 11-16, which makes it the third strongest opening along with 11-16.) White's 21-17 reply is the strongest and gives him an edge because it takes advantage of Black's hole on square 10.

• 6-10 17-13
• 7-10 17-14, 9-18 23-7 -> 26-23 (wins)
• 7-10 17-14, 10-17 22-13
• 9-13 17-14
• 9-14 17-10 -> 22-18 -> 26-10 -> 25-22 (wins)
• 11-16 17-13
• 12-16 24-19 (wins)
• 15-18 22-15 -> 23-14 -> 24-19
• 15-19 24-15 -> 22-15 (wins)