Portuguese media outlet A Bola, as quoted by the Birmingham Mail, is reporting that Manchester United are interested in the Benfica star.
The same article states that the Red Devils sent representatives to watch Benfica’s 4-0 victory over Braga.
According to the same story, Dias would be available if Manchester United or another club would be willing to meet his £80m contract release clause.
The report goes on to add that Manchester United could face competition from Wolves, who are long-term admirers of the 22-year-old.
The story does suggest that Wolves are currently being priced out of a potential deal for the highly-rated Portugal international.
Manchester United already strengthened their back four with the £80m addition of Leicester City defender Harry Maguire in the summer.
The Red Devils paid a world-record fee for a defender to sign the England international, who was previously linked with champions Manchester City.
Manchester United have already conceded four goals in four games in the Premier League this term.
Maguire is forging a centre-half partnership with former Benfica defender Victor Lindelof at Manchester United.
The Red Devils will take on Maguire’s former team Leicester in their next Premier League fixture on Saturday 14 September.
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