user: Question: What were the opponents from the April 13?
Columns: ['Date', 'Opponent', 'Score', 'Loss', 'Save']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['April 9', 'Pirates', '2 - 1', 'Rhoden (0-1)', 'Smith (1)']
SQL:

assistant: SELECT "Opponent" FROM "Table" WHERE "Date" = 'April 13';