He has also helped them win five FA Cups, three League Cups, the Champions League and the Europa League.
However, the 37-year-old has been urged to continue playing by his Italian coach.
"In the future, not to have this type of player will be a pity".
"I know I said I wanted to play regular football, but I have not ruled out Sunday being my last game and retiring".
With one game remaining, at home to Sunderland on Sunday, Antonio Conte's side have a golden opportunity to set a new mark.
JOHN TERRY scored for Chelsea before making a mistake which cost his side a goal just a couple of minutes later.
'We prepared for last season without Europe and for this season the squad wasn't big but next season we must improve our squad.
It proved to be the appetiser for a insane 90 minutes of football as the home side threw away a 3-1 lead after Daryl Janmaat and Stefan Okaka cancelled out other efforts from Cesar Azpilicueta and Michy Batshuayi.
John Terry and Frank Lampard played in Mourinho’s title winning sides
The club captain, of course, is John Terry.
"(Arjen) Robben and (Didier) Drogba in particular and ably supported by Damien Duff, who I thought was a fantastic player as well.
"I have to take my time in these 12 days to make the decision. I have to pick players that for me are in better form".
Sebastian Prodl was sent off for a second bookable offence in the second minute of stoppage time as Watford finished the contest with 10 men.
Chelsea manager Antonio Conte, hailed by the crowd with chants of "Antonio, Antonio", made nine changes from the West Brom game, mindful also of the FA Cup final less then two weeks away.
"They're friends, they're always together". I am a bit younger than some of the other guys. "Tomorrow I will investigate, but I don't think it was anything".
Conte joked the striker should have shared the food with him.
Conte said: "I'm very angry with him, because he must think to share". When I say that to people, they don't really understand it. I was suffering during the game.