Thibaut Courtois | Atletico Madrid (on loan from Chelsea)

Thibaut Courtois may not have played a single match for Chelsea, despite joining the Blues from Genk in 2011, but he has been exceptionally good with loan club Atletico Madrid over the last two-and-a-bit seasons.

The Belgium international is already one of the best goalkeepers in the world - and could soon become the very best.