Mourinho will face the Blues for the first time since he was sensationally forced out of Stamford Bridge, when Inter Milan entertain the Premier League leaders in the last-16 of the Champions League next week.
Winner: Mourinho led Chelsea to back-to-back League titles
During his three-year spell at Stamford Bridge, Mourinho won two Premier League titles, an FA Cup and the Carling Cup twice.
But since his departure, and four managers later, the Blues have tasted success just once, winning last season's FA Cup Final against Everton.
'Chelsea have suffered in the last two years, and it's no coincidence that their decline happened after I left,' the self-proclaimed 'Special One' said in an interview with Nuts Magazine.
'We had a unique relationship as a manager, players and fans, and when you break that, it's not easy to fix. They've had a lot of coaches since and maybe some didn't have the mentality for the club. Maybe they tried to change too much of what we put in place.
'I knew there was no time for a long-term plan with the owner they have at Stamford Bridge. You must win the title in your first season or say bye-bye. I gave them what they needed but I always knew it wasn't a job that would last forever. Maybe they would've been better off sticking with me than changing manager when they did.'
Top Drog! Didier Drogba scored in Chelsea's FA Cup win over Cardiff on Saturday
The Portuguese manager also added spice to the clash by insisting he doesnot expect his poor relationship with current Blues boss CarloAncelotti to improve.
Italian job: Ancelotti's Chelsea sit at the summit of the Premier League
'Ancelotti is no friend of mine andthis won't change. In England, you're shown respect if you're a foreigncoach who comes in and offers his experience and knowledge.
'But in Italy, this respect only comes if you're born as an Italian.Someone like me, the foreigner, isn't considered worthy of being here.This is why I say I was happier working in England.
'Inter haveasked me to try to win the Champions League for them, and I'll attemptto give them this - so they're stuck with me for a little while yet!Now we have to play an important couple of matches against Chelsea andthis is obviously a very special game for me.
'But I'm a part ofChelsea's history forever and they'll always be a big part of me. Let'ssee if Ancelotti can finish his time at Chelsea with a record as goodas mine!'
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