Ranking Chelsea's 5 best transfer windows

#1 The Jose Mourinho era (2004-2005)

Didier Drogba wins the Champions League for Chelsea with his final spot kick

After Ranieri failed to win the league, the board brought in a young Jose Mourinho who was fresh off his Champions League win with FC Porto.

He wasted little time in getting to work, as he made use of the financial muscle available at his disposal to buy Didier Drogba, Petr Cech, Ricardo Carvalho, Arjen Robben, Paulo Ferreira, Alex, Tiago and Mateja Kezman, spending nearly £150 million in the process.

With these signings, Chelsea immediately became world beaters as they went on to win the next two Premier League titles, building on a solid defence, team tactics and individual brilliance of players like Frank Lampard, Didier Drogba, John Terry, Petr Cech and Arjen Robben.

The players he bought formed the spine of Chelsea for a decade and more, the biggest testament being the 2012 Champions League win where Drogba scored the winning penalty, finishing the work that Mourinho started in the summer of 2004.

None of the players still play for the team but they will forever remain in the hearts of every Chelsea fan, for giving them the best years the club has ever seen.