The centre-back and captain has won everything in the 18 years since his debut for the club, and aside from six games on loan at Nottingham Forest he has not played club football for anyone else.
But that may change next season, with the 35-year-old confirming he will not stay at Stamford Bridge beyond this season.
https://twitter.com/domfifield/status/693866867400822784
Fans have been quick to pay tribute to the man they call 'Captain, Leader, Legend', and there is a sense that his presence will be tough to replace.
https://twitter.com/TyroneOwenNo1/status/693873063042117632
https://twitter.com/rtl104/status/693875442533715968
Many were quick to point out that another Blues defender may have been less deserving of a contract extension.