user: Question: What is Surface, when Opponents In The Final is "Christophe Rochus Olivier Rochus"?
Columns: ['Date', 'Tournament', 'Surface', 'Partnering', 'Opponents in the final', 'Score']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['September 21, 1998', 'Bucharest , Romania', 'Clay', 'Gabriel Trifu', 'George Cosac Dinu Pescariu', '7–6(2), 7–6(4)']
SQL:

assistant: SELECT "Surface" FROM "Table" WHERE "Opponents in the final" = 'Christophe Rochus Olivier Rochus';