For many years, Tottenham Hotspur have enjoyed having one of the most successful centre-back partnerships in world football.
Belgian duo Toby Alderweireld and Jan Vertonghen have formed a memorable centre-half pairing at Spurs.
But they will not be around forever and Mauricio Pochettino will have to start thinking about the future.
He already has one half of his new-look centre-back partnership in Davinson Sanchez.
The 22-year-old is growing into his role well and already impressing with consistent displays at the back.
But he will need a partner for the long-term future once Alderweireld and Vertonghen move on.
And the ideal candidate for the role could be Nikola Milenkovic.
The towering 6ft 5in centre-half is currently at Fiorentina, where he is shining in Serie A.
With power, physicality and aerial dominance, Milenkovic is showing maturity beyond his years and it is no surprise that he is a man in demand.
Manchester United are among the clubs likely to rival Spurs for the eight-cap Serbia international.
But Tottenham must make the first move because other big clubs across Europe will surely start looking at him.
Milenkovic is one of Europe’s brightest defensive prospects and Spurs need a successor to Alderweireld and Vertonghen.
Signing the former Partizan defender would be sensible and prudent business by the North London outfit.