Sir Alex Ferguson and Manchester United are leaving no stones unturned in their quest to topple rivals Manchester City from the top of the Premier League and mount a serious challenge to restore their reputation as a European powerhouse, particularly in the face of utter domination that Spanish giants Barcelona and Real Madrid threaten.

The club has already signed Japanese playmaker Shinji Kagawa from Bundesliga side Borussia Dortmund and English youngster Nick Powell from Crewe Alexandra but more players will need to be brought in if the Red Devils are to offer City, Barcelona and Real Madrid a genuine threat.

Malaga's U21 Spanish Star Isco

The latest player linked to the Old Trafford club is young Spanish midfielder Isco. The Spain U21 player, who was part of the country's unsuccessful men's Olympic football team at the London 2012 Olympics, is considered one of the brightest young prospects in Spain. He presently plays for La Liga outfit Malaga and under normal circumstances the club would not consider selling. However, as it happens, the Andalusian outfit is in considerable financial difficulty and have been forced to accept bids for other star players like Santi Cazorla (reportedly close to completing a £17m move to Arsenal).

Isco cost Malaga £4.7m when he moved from fellow La Liga club Valencia in July last year and has a £16m release clause in his contract and United, according to the Metro, have made informal inquiries over his availability.

United's summer of rebuilding also includes the possible capture of 19 year old Brazilian midfielder Lucas Moura, who has often been spoken about in connection with a move to Old Trafford this summer. The latest reports indicate that despite Sao Paulo's reluctance a £30m deal may have been agreed on and the player has had his medical checks completed.

Another high profile transfer target linked to United is Arsenal striker Robin van Persie. The transfer saga surrounding the Dutch striker, who scored 30 times in the league last season, has made news at every stage of this transfer period and as of now there are still three teams understood to be in the race to sign the forward - United, City and Italian club Juventus. The latest reports from that space, however, now suggest van Persie has been impressed with Arsenal's own display of ambition (Wenger has thrown his frugal spending policy out the window this transfer period and has confirmed the transfer of Lukas Podolski of Germany and Olivier Giroud of France, as well as being reportedly in discussion with Madrid to loan Turkish midfielder Nuri Sahin) and is considering staying on at the Emirates.