Marco van Basten has challenged Ruud van Nistelrooy to recapture the form which made him the most feared striker in Europe.

Although Holland eased out of the so-called 'Group of Death' with a game to spare, Van Nistelrooy's contribution was just a single goal.

The striker was a virtual spectator against Argentina on Wednesday, when he badly missed the service of rested wide-man Arjen Robben.

Having left rising star Klass-Jan Huntelaar out of his 23-man party altogether, Van Basten has only Dirk Kuyt as a plausible alternative to Van Nistelrooy, who fell out so spectacularly with Sir Alex Ferguson at the end of the season.

And, while it is highly improbable Van Basten would drop Van Nistelrooy for Sunday's crunch knockout clash with Portugal in Nuremburg, such a scenario is under consideration, with the Dutch coach clearly not happy with his senior striker's form.

"I expect more from a player of his standard," said Van Basten.

"Ruud is training well but I just feel he needs to show a little bit more.

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

Although he would not admit it, it is possible the fall-out from his row with Ferguson has affected Van Nistelrooy's form.

However, the 29-year-old has been quick to play down speculation the rift was triggered by a training ground row with Cristiano Ronaldo.

This weekend, the pair will meet for the first time since reports surfaced Van Nistelrooy reduced Ronaldo to tears with a stinging attack on the young winger.

Yet the former PSV Eindhoven man rejects any suggestion of bad blood between the pair.

"There is no problem between Cristiano and me," stated Van Nistelrooy.

"I know, he knows and everyone at Manchester United knows that. Nothing has happened between us at all. In fact, we both get along really well."