CREATE TABLE table_name_31 (opponent VARCHAR, surface VARCHAR, score VARCHAR)

Who played on clay and had a score of 6 1, 7 6?
SELECT opponent FROM table_name_31 WHERE surface = "clay" AND score = "6–1, 7–6"
SELECT "opponent" FROM "table_name_31" WHERE "6–1, 7–6" = "score" AND "clay" = "surface"