Raphael Varane has just highlighted Erik ten Hag's biggest challenge at Manchester United

When Manchester United signed Raphael Varane, many fans wondered how they were getting a Champions League-standard defender for such a reasonable price from Real Madrid, especially when Real had already lost Sergio Ramos earlier in the window. Even with only one year remaining on his contract in Madrid, £34million seemed an absolute bargain. However, now, after one season at Old Trafford, it has become clear.

As per Transfermarkt, Varane has missed 15 United games through injury this season and those included crucial fixtures against Manchester City, Liverpool and Chelsea. And in France's Nation League fixture against Denmark on Friday night, he suffered yet another injury.

The 29-year-old looks to have injured his hamstring, as he did in November when he was sidelined for eight games, and has now dropped out of the France squad and has been replaced by Liverpool centre-back Ibrahima Konate. Varane is expected to be back in time for United's pre-season training camp.

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Varane's injury troubles are a pressing issue as the best ability a player can have is availability. It doesn't matter how good the Frenchman is when he's on the pitch if he is never fit enough to enjoy a consistent run in the team. And this may add logic as to why United are looking to sign a defender this summer.

Jurrien Timber is reportedly being targeted by United. However, the Ajax defender is said to have doubts as to whether he would get enough game-time next season ahead of the World Cup.

Timber is positionally versatile and can play at right-back as well as centre-back. He would likely get minutes ahead of Diogo Dalot given how Erik ten Hag likes to utilise