11-15 24-19, 15-24 28-19, 8-11

11-15 is the strongest opening move by Black as evidenced by its use 95% of the games played between experts in go-as-you-please (GAYP = unrestricted) play. Black exits from a single corner, as opposed to a double corner, which leaves the back row more vulnerable to kingship. Also, 11-15 is a move towards the board center for maximum mobility. 11-15 is so strong that more responses have been used by White to obtain equality than in any other opening. Nevertheless, irrespective of the reply to 11-15, Black has a small theoretical edge, although all result in equality with best play. 22-18 ("Single Corner"), 23-19 and 23-18 are the strongest replies, while 22-17 is only adequate. 24-20 ("Ayrshire Lassie"), 24-19 and 21-17 are inferior.

24-19 is a weak reply that is not used much by either experts nor novices. Of the two alternate responses, 28-19 is stronger than 27-20.

• 19-15 10-19 -> 12-19 (wins)
• 19-16 12-19 -> 11-20 (wins)
• 21-17 10-15 -> 7-21 (wins)
• 22-17 11-15
• 22-18 11-16
• 23-18 11-16
• 27-24 11-16
• 32-28 11-16