Netherlands coach Marco van Basten has admitted Ruud van Nistelrooy is not certain to keep his place in the starting line-up for the last 16 game against Portugal.

The Manchester United striker has struggled for form since the start of the World Cup and was substituted in all three group matches.

Van Basten plans to recall Arjen Robben to his starting line-up after the Chelsea star was rested for Wednesday's goalless draw against Argentina, with Van Nistelrooy or Dirk Kuyt set for bench duty in Nuremberg on Sunday.

"The central position up front is a point of discussion and the chance that Dirk will start on Sunday has increased," admitted Van Basten.