Duncan Castles has claimed that Manchester United are desperate to complete a deal to sign FC Porto right-back Diogo Dalot.

The Reds are rumoured to be closing in on a £17.5 million deal to sign the Portuguese right-back this summer to compete with Antonio Valencia in the first-team, as per the BBC, and with Timothy-Fosu Mensah returning from his season-long loan at Crystal Palace, it is thought there will be enough understudies in the squad to ensure United are strong enough in the role for the future.

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Dalot, 19, has made eight appearances for Porto’s first-team since joining the Portuguese outfit in 2008.

He featured in Porto’s 5-0 aggregate loss to United’s rivals Liverpool in the Champions League round of 16 last season.

Dalot is predominantly a right-back but has been known to play on the opposite flank, which covers two positions United are trying to strengthen in this summer.

The Times reporter Castles confirmed that United are eager to get a deal over the line as fast as possible.

Speaking on the Transfer Window podcast, Castles said: “They have an outline of a deal.

“The price is €20 million. Relatively cheap considering the potential of the player. There is interest from other clubs. There is a sense Man United want to tie him down rapidly.”