The Red Devils are also believed to be keeping tabs on AS Roma midfielder Lorenzo Pellegrini.

Manchester United has reportedly had a bid of £80 million ($102.7for Kalidou Koulibaly rejected by Serie A outfit Napoli. The Red Devils' active search of an established center-back is still ongoing with the club suffering for not signing one in the summer transfer window. In the English Premier League alone, the Old Trafford outfit has a goal deficit of minus one having conceded 21 after netting 20 times.

Back in the summer, Jose Mourinho reportedly identified Tottenham Hotspur's Toby Alderweireld and Leicester's Harry Maguire as potential suitors for the center-back role. However, the Portuguese manager was unable to get the backing of the club to sign either of them before the window shut close. With the winter transfer window approaching, Manchester United reportedly tabled an £80 million bid for Koulibaly.

However, according to La Repubblica, the offer has been thrown out of the door by Napoli. It is believed that the Red Devils will taunt the Partenopei with a similar offer in January but club president Aurelio De Laurentiis maintains that any fee short of £89 million will not be entertained.

In another development, Manchester United will aim to make it a double scoop of Serie A talents by securing the service of AS Roma's Lorenzo Pellegrini. The 22-year-old central midfielder has £26.7 million ($34.3 million) release clause and the Red Devils are said to be ready to trigger it.

According to Corriere dello Sport, the Manchester club has offered to give Pellegrini an annual salary of £1.78 million ($2.6 million) – an amount twice what he currently receives at Roma. The revelations came after a meeting between the player's agent Giacomo Pocetta and Manchester United directors took place in London on Saturday.