Marcus Rashford scored Man United's opener against Chelsea
Their comprehensive defeat was greeted as gleefully among Tottenham followers as it was by their Manchester United counterparts. A result that intensified not only the championship chase but also the race for top-four places.
It is two defeats in the last four for Chelsea, no clean sheets in the last 10, while Diego Costa is going through a barren spell – no goals in his last five League games.
On top of all that, Spurs could inflict more damage on their confidence and score a major psychological blow in the title race by beating them in the FA cup semi-final on Saturday.
And they will go into that game on the back of their most insipid performance since those back-to-back defeats by Liverpool and Arsenal in September that forced Conte to change his system.
Chelsea have held something of an Indian sign over United in recent years – they had not lost to them in the previous 12 encounters, home or away.
But that all changed yesterday with United dominating the game from start to finish with a pace, aggression and tactical plan that worked to perfection.
Ander Herrera got Man United's second of the afternoon
Chelsea did not win a corner for more than an hour and failed to register a shot on target for the first time in a Premier League game since their visit to Old Trafford in September 2007.
They had to re-shuffle when Marcos Alonso pulled out feeling unwell just before the game while No1 goalkeeper Thibaut Courtois was out injured. But it is hard to believe the presence of those two would have made much difference, so good and fired up were United on the day.
There were United heroes all over the pitch but Ander Herrera enjoyed his finest hour in a red shirt. He was sent off for two cautions when United went out of the FA Cup at Stamford bridge last month – the second of the fouls being on Eden Hazard.
He must have had his worries when Jose Mourinho detailed him to man-mark the Chelsea danger man. But not only did he do that job well he took time off to make United’s first after seven minutes and score the second four minutes after the break.
The Spaniard clearly handled as he won the ball from Nemanja Matic but referee Robert Madley gave him the benefit of the doubt that it was accidental.
Get Quotes on Home Insurance
Chelse ace Marcos Alonso pulls out of warm-up against Manchester United Sun, April 16, 2017
Chelsea were forced into a last-minute change ahead of their clash with Manchester United after Marcos Alonso pulled out of the warm-up at Old Trafford
Play slideshow Getty Images 1 of 6
Marcos Alonso pulls out of the warm-up ahead of Chelsea's clash with Man United
There could be no arguments about the quality of his through pass, however, which allowed Marcus Rashford to race away from David Luiz and slot his shot past Asmir Begovic.
It was the earliest goal United have scored this season and provided a massive injection of confidence and belief in their play. The second summed up Chelsea’s miserable day. N’Golo Kante of all people was robbed by Ashley Young, who set up Herrera to fire past Begovic with the help of a deflection off Kurt Zouma’s shin.
The result stretched United’s unbeaten Premier League run to 22 games – 12 wins and 10 draws – going back to that embarrassing 4-0 defeat at Stamford Bridge in October.
After last month’s FA Cup exit, Mourinho was desperate to avoid a hat-trick of defeats to his former club. But more than any personal motive, he will just be relieved United are still fighting for a Champions League place on two fronts. After wins for Tottenham, Manchester City and Liverpool this was a game United simply had to win.
And they did in some style.