SELECT surface FROM table_23235767_1 WHERE score_in_the_final = "6–4, 6–7 (1–7) , 6–7 (4–7) , 4–6"
Apa setiap permukaan dengan skor di final 6-4, 6-7 (1-7), 6-7 (4-7), 4-6?
CREATE TABLE table_23235767_1 (surface VARCHAR, score_in_the_final VARCHAR)