user: Question: What date was Marcos Daniel the opponent?
Columns: ['Date', 'Tournament', 'Surface', 'Opponent', 'Score']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['August 15, 2005', 'Manta , Ecuador', 'Hard', 'Lesley Joseph', '6–4, 6–1']
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Opponent" = 'Marcos Daniel';