January transfer window: Top 10 transfers by value

#1 Christian Pulisic to Chelsea (£58m)

Borussia Dortmund v Club Brugge - UEFA Champions League Group A

In what is quickly turning out to be a disastrous season for Maurizio Sarri and Chelsea, the signing of Pulisic from Dortmund might turn out to be a silver lining.

Chelsea currently have Willian, Pedro, Hudson-Odoi and Hazard as options out wide. But Willian and Pedro are already in their 30's, Hazard is still a target for Real Madrid, and Bayern are hell-bent on signing 18-year-old Hudson-Odoi to replace Robben in the summer.

Signing a winger would have been on top of Sarri's wish list for the winter transfer window. They were, however, forced to loan Pulisic back to Dortmund till the summer.

This is also a great piece of business by the Germans. With the emergence of youngsters like Jadon Sancho and Jacob Bruun Larsen, and the brilliant form of more experienced stars like Raphael Guerrero and Marco Reus, Pulisic has been reduced to making just 5 starts this season in the Bundesliga.

He's still only 20 though, which gave Dortmund enough bargaining power to extract a sizeable fee from Chelsea.

Pulisic will add some much-needed pace, skill and trickery to a Chelsea attack that has been overly reliant on Eden Hazard for goals this season.