Thibault Camus/Associated Press
Given he was shipped out on loan after Chelsea signed him, Kurt Zouma's transfer in January went almost unnoticed.
The Blues snapped up the 19-year-old from Saint-Etienne, where he spent the remainder of 2013-14.
He has come through the youth ranks with Les Verts, establishing himself as a key player in the Ligue 1 side's backline.
At such a young age, experience is always vital and given he has been a regular at Stade Geoffroy-Guichard for the past couple of seasons, Zouma has a head start on many of his peers.
He may not be ready to switch roles in the Chelsea defence, but his experience to date marks Zouma out as a squad player heading into 2014-15.
Jose Mourinho will like his physicality, but Zouma is equally as talented in the more tactical aspects of the game and will slot in well as cover for Gary Cahill and John Terry.
The latter doesn't have much longer left in his career, so allowing the likes of Zouma to gain more experience at Stamford Bridge will only serve Chelsea well when the time comes and they have to replace their captain permanently.