user: Question: Which Opponent is on April 28?
Columns: ['Date', 'Opponent', 'Score', 'Loss', 'Attendance', 'Record']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['April 3', '@ New York Mets', '2-3', 'Hernández (0-1)', '54,371', '0-1']
SQL:

assistant: SELECT "Opponent" FROM "Table" WHERE "Date" = 'April 28';