The Daily Mirror, as quoted by the Daily Express, is reporting that Manchester United have set their sights on signing the Senegal international.
The same article states that Manchester United want to sign a top centre-half to partner the world’s most-expensive defender Harry Maguire in the heart of their back four.
According to the same story, the Red Devils have identified Koulibaly and Dias as two defenders capable of building a partnership with the England international.
The report goes on to say that Koulibaly is Manchester United’s top centre-half target after having held a long-term interest in the African star over the past three or four seasons.
The 28-year-old is valued at around £90m to £100m, which means Manchester United would have to smash their own transfer record for centre-half, the story adds.
The Daily Mirror claim that Manchester City are interested in Benfica defender Dias, which could make a swoop for the Portuguese star more difficult for Manchester United.
Manchester United are in 12th place in the Premier League table and a staggering 15 points adrift of leaders Liverpool FC after eight games this season.
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