user: Question: What is the opponent for the tournament of Rio de Janeiro?
Columns: ['Outcome', 'Date', 'Tournament', 'Surface', 'Opponent', 'Score']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Winner', '23 April 1984', 'Taranto', 'Clay', 'Sabrina Goleš', '6–3, 7–5']
SQL:

assistant: SELECT "Opponent" FROM "Table" WHERE "Tournament" = 'Rio de Janeiro';