Both Manchester clubs are weighing up moves for Villarreal centre-back Pau Torres, according to reports.
Manchester United are said to be on the lookout for a long-term partner for Harry Maguire.
Jules Kounde, Raphael Varane, Sergio Ramos and Tyrone Mings have all been linked with a move to Old Trafford in recent weeks.
Manchester City could also seek to bolster their defensive options when the transfer market reopens for business this summer.
John Stones has rejuvenated his career at the club this season, having seemingly been on the brink of departing before the start of the campaign.
However, Aymeric Laporte has been linked with the exit door after struggling for game time this term.
And according to the Manchester Evening News, United and City could go head-to-head for Torres.
The 24-year-old is enjoying an excellent season in La Liga, having featured in every minute of Villarreal’s campaign up to now.
The Spain international is under contract at the Estadio de la Ceramica until 2024, but he could be plying his trade elsewhere next season.
And while City do hold an interest in Torres, United are more likely to actually make a move this summer.
Varane has long been their dream target but there is a realisation at Old Trafford that the Frenchman will be difficult to prise away from Real Madrid.
Varane has just over a year remaining on his Madrid deal, but it may still prove tough for United to sign him.
Ole Gunnar Solskjaer’s side are said to view Torres as a viable alternative to the World Cup winner.
As well as both Manchester clubs, the Villarreal stopper is admired by Madrid and Bayern Munich.
Any move for Torres is unlikely to take place until after the European Championship, where the 24-year-old will hope to start for Spain.
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