CREATE TABLE table_name_91 (date VARCHAR2, tournament VARCHAR2, score VARCHAR2)

Tournament of tokyo, japan, and a Score of 4 6, 6 4, 6 4 had which date attached?
SELECT date FROM table_name_91 WHERE tournament = "tokyo, japan" AND score = "4–6, 6–4, 6–4"
SELECT "date" FROM "table_name_91" WHERE "4–6, 6–4, 6–4" = "score" AND "tokyo, japan" = "tournament"