Anthony Martial's red card midway through the second half made Tottenham's job a lot easier, but Spurs were in full control of the game ever since they fell behind to a first-minute Bruno Fernandes penalty.
A brace each for Harry Kane and Son Heung-min followed Tanguy Ndombele's equaliser for Tottenham Hotspur. Serge Aurier also scored a goal in the second half, as Tottenham went about rubbing salt on Manchester United wounds.
Here's how each player fared for both teams.
Manchester United Player Ratings
David de Gea - 4/10
He let in six goals, none of which were particularly his fault. He was left woefully exposed by those in front of him, and should not have much blame attached to him.
Aaron Wan-Bissaka - 3/10
Wan-Bissaka struggled against Son, and all game, he was left in a dilemma by the Korean's movement. Wan-Bissaka could never really get to terms with whether to move in-field and cover Son's movement, or stay wide and cover Reguilon.
Eric Bailly - 2/10
Selected above Victor Lindelof for this game, Bailly didn't cover himself in glory at all. He was caught flat-footed for Spurs's second goal, and then gave the ball away in his own penalty area for the third goal.
Harry Maguire - 1/10
Just an overall disaster from Maguire. He was the cause of all the panic in the Manchester United penalty area, and had a role to play in almost every goal that they conceded. A performance wholly opposite to what a captain is expected to deliver.
Luke Shaw - 3/10
Shaw was, like Wan-Bissaka, caught far too narrow far too often. That ensured that Serge Aurier had the freedom of that flank to himself, and eventually also got himself a goal.
Nemanja Matic - 4/10
Matic could not come to terms with Kane coming back into deeper positions to set Spurs off on attacks. The pace with which Spurs broke forward put Matc entirely out of his comfort zone.
Paul Pogba - 3/10
The penalty he conceded was a summation of the game that he had. His passing was atrocious, he got bullied by the Spurs midfielder, and had no control over anything he did.
Bruno Fernandes - 5/10
He gave United the perfect start with a perfectly-placed penalty, and almost set up a goal for Rashford with a superb through ball. He was taken off at half-time.
Mason Greenwood - 3/10
The youngster only had a couple of sights of goal when it was 11 vs 11. But after Martial's red card, Greenwood saw none of the ball anywhere near the penalty area.
Marcus Rashford - 2/10
Rashford had no real opportunities, apart from the one time that he hit the post in the first half. With Spurs monopolizing the ball in the second half, the Englishman had a lonely role up top.
Anthony Martial 1/10
He was the one who won the penalty in the first few seconds of the game, for Fernandes to put United ahead. But it was daft of him to lash out at Lamela, although he might argue that the red card was a bit harsh.
Fred - 4/10
He came on at half-time and was chasing shadows in the whole of the second half.
Scott McTominay - 4/10
Like Fred, McTominay came on at half-time and had only a chasing brief in the second half.
Donny van de Beek - 4/10
By the time he came on, the game was already over, with United training 6-1. So, it was not really the best game for him at this stage of his Manchester United career.