Chelsea are no strangers to spending massive amounts of money on players.
Roman Abramovich’s takeover of the club in 2003 was followed immediately by an avalanche of investment, and where spending over £100million on players in one transfer window is the norm for some clubs these days, back then it was seen as the ultimate sign of extravagance.
However, they have generally bought well – most of their larger purchases have tended to be solid, medium-to-long-term investments. Of course there are exceptions.

Here are Chelsea’s top ten most expensive signings:

10. Didier Drogba
Amount: £24m
Year: 2005
9. Michael Essien
Amount: £24.4m
Year: 2005
8. Cesc Fàbregas
Amount: £27m
Year: 2014
7. Willian
Amount: £30m
Year: 2013
6. Andriy Shevchenko
Amount: £30.8m
Year: 2006
5. Eden Hazard
Amount: £32m
Year: 2012
4. Diego Costa
Amount: £32m
Year: 2014
3. N’Golo Kanté
Amount: £32m
Year: 2016
2. Michy Batshuayi
Amount: £33m
Year: 2016
1. Fernando Torres
Amount: £50m
Year: 2011

Source: http://www.ngcube.com/top-ten-most-expensive-chelsea-signings-ever/