user: Question: Which Opponent has a Record of 45–21–4?
Columns: ['Game', 'March', 'Opponent', 'Score', 'Record', 'Points']
Types: ['real', 'real', 'text', 'text', 'text', 'real']
Sample row: [64.0, 2.0, '@ Edmonton Oilers', '1–2 OT', '41–19–4', 86.0]
SQL:

assistant: SELECT "Opponent" FROM "Table" WHERE "Record" = '45–21–4';