The Belgium international has spent six seasons at the west London outfit following his big-money move to Chelsea FC from Ligue 1 side Lille in 2012.
Hazard has played under Rafael Benitez, Mourinho, Guus Hiddink, Antonio Conte and Maurizio Sarri during his spell at the Blues.
The 27-year-old has won two Premier League titles – under Mourinho and then Conte – to establish himself as one of England’s top footballers – if not the best.
Hazard has flourished in Sarri’s team so far this season after the Italian head coach significantly relieved the Belgium international of his defensive responsibilities.
Indeed, the Chelsea FC number 10 has scored seven goals in eight games to produce some of his best football of his Blues career so far.
Reports in the English media hinted that Hazard had a complicated relationship with Mourinho during his two and a half seasons under the Portuguese head coach.
Mourinho often spoke of Hazard’s duty to track back and support his full-back in his Chelsea FC team.
But Hazard has revealed that he regrets that Mourinho’s second spell at Stamford Bridge was cut short after the Blues made a disastrous start to the defence of their league crown in 2015-16.
“I don’t regret many things in my career, but that I have not been able to work with Mourinho at Chelsea anymore is one of them,” Hazard told Belgian outlet HLN.
“We had a team that could win more trophies. We just ended up in a negative cycle.”
Hazard added: “I sent him a message to say I was sorry he had gone and that I was sorry.
“We’d enjoyed all that success together, but this time we hadn’t. I felt a little bit guilty because I’d been player of the year.
“I’d been one of the most decisive players, and then I performed less.”
Hazard scored his seventh Premier League goal of the season in Chelsea FC’s 3-0 victory over Southampton in their last top-flight fixture before the international break.
The Chelsea FC number 10 will face his former manager Mourinho in their next Premier League fixture when Manchester United take on the second-placed side at Stamford Bridge on Saturday evening.
Hazard has been linked with a potential move to Mourinho’s former employers Real Madrid in the opening months of the season following his sensational start to the campaign.
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