Manchester United have signed fullback Diogo Dalot from Portuguese champions Porto.

Dalot only made his first-team debut in February but the 19-year-old has moved to Manchester on a five-year deal, with an option for a further year, after Premier League runners-up United activated his release clause.

With out-of-favour Italian Matteo Darmian expected to leave Old Trafford and manager Jose Mourinho desperate to provide veteran right-back Antonio Valencia with more competition, United have turned to the Portugal U21 international.

👋 A big #MUFC welcome to @DalotDiogo!#BemvindoDalot 🇵🇹 pic.twitter.com/kYPAfmdapk

— Manchester United (@ManUtd) June 6, 2018

‘Joining Manchester United is an unbelievable opportunity for me,’ Dalot said in a statement on United’s website.

‘I have grown up in Porto’s academy and I am so thankful for everything they have done for me. But the chance of coming to the biggest club in the world is something I just couldn’t turn down.

‘I’m excited about working with Jose Mourinho and learning everything I can from such a successful coach. I am looking forward to playing alongside the fantastic players in the squad.’

Dalot made seven appearances in all competitions in 2017-18 as Porto won the Primeira Liga crown for the first time since 2012-13 and reached the Champions League’s last 16.

The defender played in six matches of Sergio Conceicao’s triumphant domestic campaign, which ended Benfica’s run of four successive league crowns.

Dalot also played at left-back in Porto’s goalless draw in the second leg of their Champions League tie with Liverpool, who won 5-0 on aggregate in March.

The news comes a day after United announced they had reached an agreement to sign Brazilian midfielder Fred from Shakhtar Donetsk.