user: Question: What day was the surface Clay and the score 6–1, 6–4?
Columns: ['Date', 'Tournament', 'Surface', 'Opponent in the final', 'Score']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['13 June 2004', 'Alcobaça', 'Hard', 'Lucía Jiménez', '7–5, 5–7, 6–1']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Surface" = 'Clay' AND "Score" = '6–1, 6–4';