Sir Alex Ferguson
Sir Alex Ferguson tops the rich list. REUTERS

Manchester United boss Sir Alex Ferguson, despite being busy preparing for his side's league derby against title rivals Manchester City, is reportedly also working on signing Sao Paulo's attacking midfielder Lucas Moura, according to a Metro report.

However, there is also interest from Chelsea and Spanish club Real Madrid and because of the interest (Italian outfit Inter Milan are also credited with that interest), the 19 year old player's value has been set at £40 million. The player has a £65 million release clause in his contract.

Moura is considered one of the brightest young talents in Brazil and South America and is also being targeted by Paris St Germain and Barcelona. The interested clubs have reportedly sent scouts to keep an eye on the teenager.

"Inter, Chelsea and Manchester United have already been in contact with me about him," Wagner Ribeiro (Moura's agent) told Globo Esporte, according to the Metro. However, Sao Paulo's valuation of their player's worth has put a crimp in the plans of all those interested.

Apart from Moura, Ferguson is tracking Icelandic midfielder Gylfi Sigurdsson, who is on loan at Swansea City from German club TSG 1899 Hoffenheim, according to the Mirror. A fee of about £10 million is being spoken about. Manchester United assistant manager Mike Phelan, along with chief scout Martin Ferguson, were reportedly at the Reebok Stadium last week, to monitor the 22 year old's performance against Bolton.

The Red Devils, who were forced to recall retired veteran Paul Scholes after injuries robbed them of several midfield options, will be very keen on signing Sigurdsson, who has scored seven goals in 14 appearances for the Swans so far. However, Hoffenheim will be trying to get a little more than £10 million from the Red Devils for Sigurdsson, who transferred from Reading to the German club for a fee of £7 million in 2010.