Manchester United are on the lookout for a new centre-half as doubts continue over Victor Lindelof.
The Swede has been Harry Maguire's most regular partner in the heart of United's defence but his form has been up and down.
But keeping clean sheets has proved challenging for the Red Devils and summer targets are being considered.
Ole Gunnar Solskjaer spent over £70m on Maguire last summer but has opted to play several squad members alongside him.
Despite referring to Lindelof as a "leader" earlier this season the United manager is looking to strengthen a host of areas this summer.
The coronavirus pandemic is not going to cripple the Red Devils financially like it will some of their rivals.
It means the likes of Jadon Sancho and Jack Grealish remain targets as Old Trafford.
But enquiries have been made about Real Valladolid defender Mohammed Salisu, reports ESPN.
The 21-year-old is one of the centre-halves being considered by United.
Solskjaer will also have to decide which players are part of his long-term plans.
Lindelof signed a long-term contract at Old Trafford in September and Eric Bailly's contract has been extended by a further two years.
Chris Smalling has spent the season on loan at Roma with the Italian club keen to keep him at the Stadio Olympico.
Phil Jones has had to settle for just two league starts while academy product Axel Tuanzebe is still firmly part of the Norwegian's plans.
United's executive vice-chairman Ed Woodward has told fans not to expect a summer of mass spending though despite the club's wealth.
He said: "Nobody should be under any illusions about the scale of challenge facing everyone in football and it may not be ‘business as usual’ for any clubs, including ourselves, in the transfer market this summer."
"As ever our priority is the success of team, but we need visibility of the impact across the whole industry, including timings of the transfer window, and the wider financial picture, before we can talk about a return to normality."
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