Dalot has only made seven first-team appearances for Porto but United's scouts have been sufficiently impressed by the performances to make a move for the 19-year-old.
The Daily Mail report that the 19-year-old has a buy-out clause of £17.4m and the Red Devils are looking to trigger it. Deployed in an unfamiliar role as the left-back - the player is a natural at right-back - Dalot seemed unfazed by the step up and put in credible shifts.More news: Chennai Super Kings vs Sunrisers Hyderabad
Matteo Darmian, who has been a reserve for Mourinho in both full-back slots, is expected to leave, so Dalot is seen as a replacement for the Italian and as a challenger for Valencia's first-team berth. Today, Man Utd are set to sign Diogo Dalot...
Dalot has represented Portugal from under-15 to under-21 level and made his Porto debut in October.More news: North Korea summit cancellation a setback to dealmaker Donald Trump
Ashley Young, primarily a winger, was used at left-back on numerous occasions last season, but the United boss is said to want a more traditional defender on the left side of his back four.
This deal has come from nowhere but the Telegraph says United have moved fast to get an agreement wrapped-up as they faced competition from the likes of Real Madrid, Barcelona, Juventus and Napoli.More news: Everything To Know About Deadly Nipah Virus
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