The Frenchman arrived in the summer of 2016 from Lyon as a raw talent, but has blossomed into a complete centre-back during his short time in Spain.
Manchester City were reportedly looking into a deal for the 24-year-old in the summer and now, the red half of Manchester are setting things into motion for what would be one hell of a signing.
His latest all-conquering display in Barca's 1-0 win over La Liga title rivals Atletico Madrid only further enhanced his reputation, with him and Gerard Pique expertly marshalling Antoine Griezmann and Diego Costa.
The capture of Alexis Sanchez was big, but Umtiti - a player they desperately need - would be even bigger.
Sport (h/t Metro) reported United are willing to meet Umtiti's €60 million (£53.4 million) buyout clause, and Mourinho is personally campaigning to convince the defender to move to Old Trafford.
United are willing to meet Umtiti's buyout clause and have offered a contract which is worth double what he is now earning with Barca.
It is claimed Mourinho is letting him know of his love through France team-mates Paul Pogba and Anthony Martial.
Talks are underway, and Umtiti wants from the Catalan giants what United are prepared to pay - £8m a year.
Sport report that his brother and representative, Yannick, has met with United chiefs on several occasions.