According to The Sun, Man United manager José Mourinho has been given the green light to sign Tottenham's Toby Alderweireld in January. 

With the Belgian's contract due to expire at the end of the season, it has long been rumoured that he will depart soon, with Tottenham wanting to make something from his sale rather than letting him go for free.

The defender has also made it no secret that he wants to leave the club, despite still putting in resolute performances for The Lilywhites whenever manager Mauricio Pochettino has called upon him.

Man United believe that they could get Alderweireld for £40m, which, given Tottenham's potential period of austerity due to the new stadium, may be an offer than chairman Daniel Levy cannot refuse.

However, it has been seen this season that Tottenham can look slightly bare in defence even with Alderweireld. Injuries to both Jan Vertonghen and Dávinson Sánchez have meant the club have needed to rely on 20-year-old Juan Foyth. While the Argentinian has looked like he will be a high-quality player for years to come, he is perhaps to error-prone at the moment for Pochettino to rely on him.

If Alderweireld were to go in January, and Spurs don't buy a replacement, they would really be looking at only two top-level defenders in Vertonghen and Sánchez. For a club that are seeking to compete in as many competitions as possible, this may not be good enough.

This is the unenviable decision that Levy has to make; while the cash-injection would be hugely beneficial, it could cost Tottenham dearly come the end of the season.