Ole Gunnar Solskjaer is targeting RB Leipzig defender Dayot Upamecano to bolster his defensive options at Manchester United, sources have told ESPN, after sealing a deal to make Ajax midfielder Donny van de Beek his first major signing this summer.

Netherlands international Van de Beek is expected to complete a £40 million move to Old Trafford this week after agreeing terms with Ajax over the weekend. United have been pursuing the 23-year-old since January.

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But with United continuing to make slow progress in their attempts to land priority target Jadon Sancho from Borussia Dortmund due to the pay demands of the England winger and his representatives, United manager Solskjaer wants to intensify efforts to boost his squad before the team's Premier League opener against Crystal Palace on Sept 19.

Sources have told ESPN that Solskjaer is now prioritising the addition of a top-quality centre-half to play alongside captain Harry Maguire and Upamecano is the top target.

The 21-year-old impressed during Leipzig's run to the Champions League semifinals in Lisbon earlier this month having just signed an extension to his contract until June 2023.

He had been due to be out of contract in June 2021 -- a deal which included a €60m release clause -- but despite committing his future to Julien Nagelsmann's team, reports in Germany claim that the new deal includes a release clause of €42m, which can be triggered at the end of the 2020-21 season.

Solskjaer wants to recruit during this window, however, and sources have told ESPN that there is a belief that a deal could be struck with Leipzig before the Oct. 5 transfer deadline.

United expect to offload a number of their defenders during the transfer window, with Marcos Rojo, Chris Smalling and Phil Jones all heading for the exit door at Old Trafford.

But with Solskjaer also concerned about the reliability of Eric Bailly and Victor Lindelof, and the fitness record of youngster Axel Tuanzebe, the signing of a new centre-half has become of even greater importance.