user: Question: Which opponent had a round of SF?
Columns: ['Date', 'Round', 'Opponent', 'Venue', 'Result', 'Attendance']
Types: ['text', 'text', 'text', 'text', 'text', 'real']
Sample row: ['27 January 1996', 'R3', 'Keith', 'A', '10-1', 15461.0]
SQL:

assistant: SELECT "Opponent" FROM "Table" WHERE "Round" = 'SF';