CREATE TABLE table_name_40 (surface VARCHAR, score VARCHAR)

What is the surface of the score, 7 6 (7 3) , 6 3?
SELECT surface FROM table_name_40 WHERE score = "7–6 (7–3) , 6–3"
SELECT "surface" FROM "table_name_40" WHERE "7–6 (7–3) , 6–3" = "score"