user: Question: Who was the opponent at the game when the record was 15–15?
Columns: ['Date', 'Opponent', 'Score', 'Loss', 'Attendance', 'Record']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['May 1', 'Red Sox', '6–5', 'Drese (2–3)', '49,342', '12–14']
SQL:

assistant: SELECT "Opponent" FROM "Table" WHERE "Record" = '15–15';