England captain David Beckham trained with the rest of the squad on Wednesday less than 24 hours after a scan on a back injury.

His return means Beckham will almost certainly be available for Saturday's World Cup Group Six qualifier against Northern Ireland at Old Trafford.

Teenage striker Wayne Rooney, who also trained at Manchester United's Carrington complex, will lead the England forward line in the qualifier despite a police investigation into an alleged assault by the player.

Manchester police said on Tuesday a member of the public had made a formal complaint of assault by the 19-year-old United forward after an incident in a city centre nightclub.

Rooney will be able to play for England as the Football Association has reviewed its procedures since dropping striker Alan Smith from the squad in November 2003 following his arrest in a police enquiry.

Smith, who had been hoping to play in a friendly against Denmark, was arrested and released on bail over an alleged bottle-throwing incident during a League Cup game for his former club Leeds against his present club Manchester United.

No charges were subsequently brought against Smith.

A charge will not be enough to prompt the FA to drop Rooney from Saturday's game or the qualifier in Newcastle the following Wednesday against Azerbaijan. His removal would only occur if a case against the player was proven.

Local media alleged Rooney hit a 22-year-old student who taunted him early on Tuesday over his controversial transfer from Everton last August.

Many Everton fans were angered by the 27 million pound move to United, which they saw as an act of betrayal.

England are top of Group Six going into the two games in their bid to reach next year's finals in Germany.