CREATE TABLE table_36483 ("Date" TEXT, "Tournament" TEXT, "Surface" TEXT, "Opponent in the final" TEXT, "Score" TEXT)

What tournament did Smeets play against Mark nielsen?
SELECT "Tournament" FROM table_36483 WHERE "Opponent in the final" = 'mark nielsen'
SELECT "Tournament" FROM "table_36483" WHERE "Opponent in the final" = 'mark nielsen'