Manchester United bolstered their Premier League title aspirations by demolishing Leeds 6-2 in the first league meeting between the sides for 16 years on Sunday.
Scott McTominay and Bruno Fernandes scored twice as United's counter-attacking threat tore apart Marcelo Bielsa's attacking approach to move the Red Devils up to third, five points behind leaders Liverpool with a game in hand.
"It could have been 12-4, it was that kind of game. It was fantastic from the first minute," said United boss Ole Gunnar Solskjaer.
"We had a plan to get after them, go forward and Scott gets two goals in the first three minutes."
The much-anticipated clash as a historic rivalry was renewed lacked the fervour of a full Old Trafford in the stands, but more than delivered on the field.
United have made a series of slow starts this season, but put the result almost beyond doubt inside three minutes thanks to two goals from McTominay.
The Scotland international burst forward from his deep role in midfield to smash home Fernandes's pass from outside the area and then slotted home Anthony Martial's through ball.
Bielsa was among the finalists for FIFA's coach of the year this week for guiding Leeds back to the top flight.
However, the Argentine's determination to play in the same wide-open style no matter the opposition backfired as the visitors were 4-0 down inside 37 minutes.
"Whether it is 5-0, 0-5, or 0-0, you know it is going to be frantic and hectic because they have an attitude and style that makes you have to work and you have to earn it," added Solskjaer.
"Just imagine if that had 75,000 people here. It would have gone down as one of the best Man Utd performances against Leeds."
Fernandes pounced on a loose ball inside the area after another fast counter-attack to make it 3-0 before another Leeds' Achilles' heel, defending set-pieces, was exposed when Victor Lindelof swept home Martial's flick on from a corner.
Leeds had plenty of chances themselves at the other end as Patrick Bamford slashed wide when clean through on David De Gea when the score was at 2-0.
"In a big game like this, a derby, where it means so much to the club and the fans, I'm almost glad the fans weren't allowed in to watch that because it would have felt even worse sending them home after watching that," said Bamford.
"It could have been 6-6 if you're an optimistic Leeds fan or it could have been 10-2. We couldn't do ourselves justice."
Leeds did get on the scoreboard four minutes before half-time when captain Liam Cooper headed in off the inside of the post from a corner.
Daniel James came within minutes of becoming a Leeds player in the January transfer window of 2019 before his move from Swansea collapsed and the Welsh international moved to United six months later.
Solskjaer handed James a rare start, knowing his speed on the break would cause problems, and he got his reward for an impressive display when he latched onto McTominay's pass to drill low past Illan Meslier for United's fifth 24 minutes from time.
Moments later Leeds had been hit for six as Martial was upended inside the penalty area and Fernandes rolled home United's 10th penalty of the season.
The scoring did not stop there as Stuart Dallas fired a wonderful effort into the top corner to the Leeds deficit.
Meslier made a series of late saves to deny United matching Liverpool's seven-goal thrashing of Crystal Palace on Saturday, while Jack Harrison should have added another for Leeds late on as a breathless encounter ended with 43 attempts on goal.
United had previously struggled to match their perfect away form in the league this season, but just a second win in seven games at Old Trafford propels Solskjaer's men back into title contention as Tottenham, Chelsea and Manchester City have dropped points in the past week.
Defeat leaves Leeds still in 14th, but with a seven-point cushion above the relegation zone.