เกมนี้เล่นบนพื้นผิวใดด้วยคะแนน 6–4 6–4?ไม่จำเป็นต้องใช้โต๊ะทั้งหมด
On what surface was the game played with a score of  6–4 6–4?It is not neccessary to use all the tables.
 table_177273_2:  (surface [ VARCHAR ] score [ VARCHAR) ]
SELECT surface FROM table_177273_2 WHERE score = "6–4, 6–4"