Paris, July 21 : Franck Ribery and Karim Benzema face a difficult future as fans and one of the top names in French football deserted the players after they were placed under investigation on suspicion of having had sex with an under-age prostitute.

Fernand Duchaussoy, who is expected to replace Jean-Pierre Escalettes as national football federation boss when the FFF president steps down from his post Friday, made clear his scepticism about the players' international prospects.

"I don't see how a player, who is under judicial investigation, can be nominated for the France team," he said.

Bayern Munich midfielder Ribery and Real Madrid striker Benzema were taken before an investigating magistrate Tuesday after being questioned for seven hours by investigators from the Brigade for the Repression of Procuring.

However, Ribery's lawyer Sophie Battai told the Europe 1 radio station Wednesday that she intends filing for the case to be struck out, adding that the scandal had seriously affected her client.

"He is distraught," she said.

Ribery's club have so far stood by the 27-year-old, who is due to return to Munich on Sunday before continuing his recovery programme Monday following a groin operation.

"I hope that he can return to team training as soon as possible and that this painful issue is soon over," said Bayern sporting director Christian Nerlinger Wednesday at the German champions' training camp in Arco, Italy.

Police stepped in after receiving statements by a self-styled professional escort, Zahia D., who had told police that Ribery and Benzema had paid for sex with her when she was a minor.

She was 16 in 2008 when she allegedly had relations with Benzema, and 17 when she supposedly flew to Munich to spend a night with Ribery the following year.

However, Zahia D. has repeatedly said that the two players did not know that she was a minor at the time.

In French law, to be placed under investigation is a step preliminary to being charged with a crime, and sex with an under-age prostitute is punishable by up to three years in prison and a hefty fine.

The L'Equipe newspaper greeted the action of the police, saying there would be consequences for Ribery and Benzema and that the era of "untouchable" French footballers was at an end.

"Nothing is stopping them from carrying out their footballing duties but there must be major question marks over their psychological health for Bayern Munich, Real Madrid and (new France coach) Laurent Blanc," the paper wrote.

In an opinion poll carried out by the internet portal le10sport.com, nearly 90 per cent of fans voted for Ribery and Benzema to be excluded from the national team. (DPA)