Manchester United have opened negotiations with Everton over a deal for Marouane Fellaini, as David Moyes fears that his top midfield target, Cesc Fábregas of Barcelona, could prove out of reach.

Moyes, who has so far added only the young Uruguayan full-back Guillermo Varela to his squad before his debut season at Old Trafford, worked with Fellaini at Everton, having signed him for £15m from Standard Liege in 2008.

Fellaini is understood to have offers from elsewhere in the Premier League but the 25-year-old would relish the opportunity to join United and continue his working relationship with Moyes. United are in pole position for his signature. Fellaini's Everton contract contained a £23.5m buyout clause but this expired on 31 July, meaning that his value will determined by the market.

United's need for reinforcement in midfield has been intensified by Paul Scholes's retirement at the end of last season and Moyes has pushed to take Fábregas, the former Arsenal captain, seeing two bids turned down by Barcelona. Moyes has also been linked with a move for Luka Modric of Real Madrid although that, too, has been fraught with complications.

Arsène Wenger, the Arsenal manager, has said for the past three weeks that his information was that Fábregas would stay at Camp Nou for at least another season. Despite the acrimony of Fábregas's departure from Arsenal, Wenger has retained a good relationship with him while the player's agent is the son of David Dein, Wenger's closest contact in the game. In this summer of the contractual transfer clause, Arsenal have one that effectively entitles them to first refusal on Fábregas. Wenger's information would appear to be well-sourced.

Fellaini is a different type of midfielder, with reservations over his passing ability and disciplinary record. But he has skill, tremendous presence and threat, as evidenced by his 12 goals for Everton last season.