user: Question: what was the name of the team opponent to Elfsborg
Columns: ['Team', 'Contest and round', 'Opponent', '1st leg score*', '2nd leg score**', 'Aggregate score']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Rosenborg', 'Champions League 2nd Qual. Round', 'Breiðablik', '4-0 (H)', '0-2 (A)', 'W 4–2']
SQL:

assistant: SELECT "Team" FROM "Table" WHERE "Opponent" = 'Elfsborg';