Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_57628 ( "Outcome" text, "Date" text, "Tournament" text, "Surface" text, "Opponent in the final" text, "Score" text )

### Question ###
In the surface of clay who was the opponent in the game resulting in a score of 6 4, 6 4?

### Accurate SQL ###

SELECT "Opponent in the final" FROM table_57628 WHERE "Surface" = 'clay' AND "Score" = '6–4, 6–4'