The Sun is reporting that both the Red Devils and the Spanish giants are interested in signing the 22-year-old defender to bolster their squads ahead of next season.
The France Under-21 international has been in impressive form for Sevilla this season and both Barca and United are thought to be keen on signing him.
The defender has scored three goals and made one assist in 30 La Liga games for Sevilla so far this season.
The same report says that FC Barcelona have already made an enquiry about signing Lenglet this summer, and it is also claimed that he could cost around £20m.
According to the same story, Red Devils boss Jose Mourinho could be willing to let both Marcos Rojo and Phil Jones leave Old Trafford as he looks to revamp his squad.
And Lenglet could be one of Manchester United’s top defensive targets ahead of the new season.
Meanwhile, Manchester United booked their place in the FA Cup final on Saturday thanks to a 2-1 comeback win over Tottenham at Wembley.
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