Goals from Pedro, Gary Cahill, Eden Hazard and N’Golo Kante made Mourinho’s first return to west London since being sacked by the Blues just under a year ago a torturous experience.
Antonio Conte rubbed salt into Mourinho’s wounds by stirring up the crowd during the closing stages of the match - something which clearly irritated the Chelsea boss, judging by his reaction in the seconds after the final whistle - and United are now priced at 20/1 with some bookmakers to finish the season as Premier League champions.
However, this isn’t the heaviest defeat of Mourinho’s managerial career.
Back in November 2010, a few months after Real Madrid appointed Mourinho as manager, Los Blancos suffered a humiliating 5-0 defeat against Barcelona at the Camp Nou.
Real Madrid still finished second that season
Inspired by Lionel Messi, Pep Guardiola’s side outclassed their fierce domestic rivals while the performance outlined the huge gulf in class between the two teams.
The 2010-11 campaign, though, wasn’t a total disaster for Real Madrid. In the end, they only finished four points behind Barça in second position.
Dudek reveals what Mourinho told Madrid players
But was the fact Madrid remained competitive down to Mourinho’s reaction after the team’s defeat at the Camp Nou?
Jerzy Dudek, the former Liverpool goalkeeper who was on the bench for Madrid that night, revealed in his autobiography ‘Under Pressure’ what Mourinho told the players in the away freezing room after the match.
“5-0, can you believe it? Barcelona won 5-0. It was the pogrom,” Dudek said. “After the match in the locker room there was total chaos. Some of us were crying, some were quarrelling, some were looking at the floor.
“Then Mourinho came in. He knew how bad it was but he looked at us and said: ‘I know this hurts you. Perhaps for most of you it is the worst loss of your entire career. They are happy now and seem to have won the championship, but have only won one game. This is just the beginning. There is still a long way to get the title.
‘Tomorrow I will give you the day off, but do not stay in your houses. Go with your families, children or friends for a walk around the city. Let people see that you can overcome this. Perhaps people talk about the significance of this defeat, but do not hide behind it. You must show your balls. After this defeat, we must fight for the title’.
“We rose after this disaster quicker than anyone expected. I understood for the first time how important psychology was in sport. How much you can gain or lose. And what an expert psychologist Jose Mourinho is.”
Did Mourinho also console the United stars?
We can only speculate that Mourinho may have used similar tactics in the visitors’ dressing room at Stamford Bridge at the weekend.
However, the 53-year-old publicly hit out at his defenders for producing a series of individual errors during Sunday’s match.
Guardiola’s Barcelona is arguably the best team of all time; Conte’s Chelsea are obviously nowhere near that level.
But United made their opponents look like world beaters - and Mourinho, humiliated, just about managed to hide his emotions on the touchline.
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