Manchester United are in an advanced stage of signing Fabinho from AS Monaco in the summer transfer window.

According to the Spanish publication Marca, the player was keen on joining Atletico Madrid. The Court of Arbitration of Sports (CAS) upheld the Spanish capital club's appeal against the transfer ban.

Atletico are unable to register players in the summer and that ended Fabinho's chances of making a switch to the La Liga. The situation has forced him to look at the interest of other clubs in the market.

United are not the only club interested in signing the Brazil international. Their league rivals Manchester City are also in the race for his signature as Pep Guardiola is keen on the Monaco star, according to the Sun.

It is believed that the Red Devils are ahead of City in securing the services of Fabinho this summer. The 23-year-old has been a key player in Leonardo Jardim's side this season as the French club won the league for the first time since 2000.

Fabinho's contract at Stade Louis II runs down in 2021 and can play as a right-back as well as a defensive midfielder. His versatility has attracted United manager Jose Mourinho, who is interested in bringing the South American star to Old Trafford.

The player joined Monaco on a season-long loan from Real Madrid in the summer of 2013. He extended the loan deal for one more season before completed a permanent switch two years later in 2015.

When Fabinho was at the Spanish capital club, Mourinho promoted him to Real's first team and handed him his first team debut against Malaga in the 2012/13 season. The CAS' decision to uphold Atletico's transfer ban could allow the Portuguese tactician to reunite with his former player at United, who is valued at £50m ($34.7m), reports the Sun.

Fabinho has been linked to Manchester United and Manchester City Getty