Mourinho had two spells at Chelsea winning the Premier League and League Cup on three occasions and the FA Cup.
But his hero status at Stamford Bridge suffered a blow when he became United manager.
On his first return in October, Mourinho was humiliated as his United side were thrashed 4-0.
Then when the two sides met again in the FA Cup in March, Mourinho was taunted by Chelsea fans.
However in April, Mourinho was able to turn the tables on Chelsea supporters.
Jose Mourinho celebrates in style after Manchester United's Europa League win Wed, May 24, 2017
Jose Mourinho was very happy after Manchester United won the Europa League!
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Jose Mourinho celebrates in style after Manchester United's Europa League win
I did it because it was Chelsea and I wanted to make clear I’m not Chelsea anymore
When United beat Chelsea 2-0 and after the final whistle he repeatedly pointed to the United badge on his tracksuit.
And Mourinho says he did that to show his loyalty is now with United.
He told BT Sport: “I come with the tracksuit, which normally I don’t do. I did it because it was Chelsea and I wanted to make clear I’m not Chelsea anymore.
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Jose Mourinho made his feelings about Manchester United clear
“Chelsea is in my history, I’m in Chelsea’s history, I have huge respect for the fans, they gave me so much, but I’m not Chelsea any more.
“So I came with the tracksuit because it has the badge and I could show everyone my feelings.
“Yes, it was calculated beforehand. I did it because I wanted to finish with my connection to Chelsea. It was just about the history.
”If one day I’m not at Manchester United and I move to another cub I will do exactly the same. Because it’s about being a super professional and that I am.”