Manchester United are reportedly considering alternatives to Real Madrid defender Raphael Varane.
The France international has just 12 months remaining on his contract at Los Blancos, who he has represented since 2011.
The 28-year-old is keen to take on a new challenge, leading to strong interest from United at a time when they require reinforcements in the middle of their backline.
While numerous reports have suggested that United are clear favourites to wrap up a deal, Diario AS claims that the Premier League outfit have doubts over whether a transfer will be completed.
With Real currently against accepting a cut-price fee for the player, United are said to have identified a number of different options.