The club have been determined to bring in a leader in that area for some time, with the necessity for such a figure persisting past Jose Mourinho's departure, and only emphasised by the 2-0 Champions League defeat by Paris Saint-Germain on Tuesday.
The top current targets are Skriniar, Napoli's Kalidou Koulibaly and Sampdoria's Joachim Andersen. While Andersen is seen as likely to go to Tottenham Hotspur, with contact and progress having already been made there, Koulibaly could be very difficult to extract from Napoii. A new Inter contract has been discussed for Skriniar, but his camp have also been aware of United's long-term interest.
It is understood that Ole Gunnar Solskjaer has had some input over potential summer signings.
Any purchase will see one of the current centre-halves moved on. Chris Smalling and Phil Jones having recently agreed new deals, so Eric Bailly is seen as under threat.
The Ivorian is understood to have split opinion among United's staff. While some believe he has a physicality that has been missing, others worry about his purer footballing ability.
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