English FA Premiership: Alex Ferguson has identified Nemanja Vidic, Manchester United's expected £7 million signing from Spartak Moscow, as a prospective new partner for Rio Ferdinand in the centre of defence.

The deal is likely to see Mikael Silvestre move to left-back in the new year, with John O'Shea facing a prolonged spell on the sidelines.

"We've been watching him for some time and he's been very impressive," Ferguson said. "He's quick, he's aggressive and he's a good passer of the ball, with good physical attributes. So all the vital parts are there. What we have to do is give him a crash-course in English, because his language is only limited."

Provided Vidic (24), passes a routine medical examination, he will complete his transfer on Sunday and will be available for United's trip to Arsenal the following Tuesday. Ferguson might not include him straight away, but the longer-term plan is for Silvestre to fill Gabriel Heinze's left-back role, reverting to the position he initially played in for the club when he signed from Internazionale six years ago.

Silvestre has been virtually ever-present since that move but, looking ahead to next season, the former France international may have to face up to his first experience of no longer being a first-team player when Heinze is fit again.

Silvestre's form has not come under as much scrutiny as Ferdinand's, but he has been the shakiest member of United's back four over the last year and Ferguson has begun to have misgivings.

Vidic, a regular for his national team, is regarded as the aggressive type of centre-half the club have missed since Jaap Stam's departure. United had to fend off competition from several clubs, most notably Liverpool and Fiorentina, before securing the transfer. Liverpool's manager Rafael Benitez is understood to be bitterly disappointed to have missed out and United had desperately tried to keep the transfer quiet for fear of alerting Chelsea.

* Guardian Service