Brighton survived a late onslaught to secure a first win at Old Trafford and condemn Erik ten Hag to a losing start as Manchester United manager.
Pascal Gross’ first-half double stunned the home supporters, who were desperate to see their team put a miserable end to last season behind them.
However, United were totally outplayed in that opening period by Graham Potter’s side, who beat them 4-0 at the Amex Stadium in May on their way to a ninth-placed finish, their highest in history.
Not even the second-half introduction of Cristiano Ronaldo could deny Brighton, although United did threaten a comeback when a scramble inside the visitors box ended with Alexis Mac Allister turning the ball into his own net after goalkeeper Robert Sanchez had touched it into his path under pressure from Harry Maguire.
In nine previous league visits, Brighton had managed only one draw, so this victory was historic.
New season, same problems for Man Utd
With the sun shining and a new manager in place, there was a sense of optimism around United before kick-off.
Ten Hag has started to impose his personality on the club, to the extent of ousting some of the ‘prawn-sandwich brigade’ from their corporate hospitality suites so his players could have their pre-match meal.
Yet so many of the old issues remained. Protests against the United owners before kick-off meant the club shop had to be shut.
Co-chairman Avie Glazer was paying a rare visit and would have heard the songs to his left calling for his family to get out of the club.
On the pitch, there was no cohesion despite decent debuts from Christian Eriksen and Lisandro Martinez.
Brighton, well drilled and fluid, took advantage. Leandro Trossard volleyed into the side-netting within 15 seconds of the start and United failed to impose themselves on the game until it was far too late.
For the opener, Welbeck’s run split Maguire and Martinez. The latter came across from the left to cover the cross, leaving a huge hole in the six-yard box and, as United’s defence scrambled to plug the gaps, Gross was on his own to tap home at the far post.
He was in a similar position but on the other post when Solly March cut inside and unleashed a low shot, which keeper David de Gea turned into his path.
The boos that accompanied the half-time whistle were predictable and deserved. Within eight minutes of the resumption, Ronaldo had been introduced to try and lead a rescue mission.
The 37-year-old had a negligible impact. It was another Portuguese, Diogo Dalot, who created the confusion that led to United’s goal. But by the end it was Brighton who looked more likely to score again.
Potter’s fabulous job
Amid the inevitable soul-searching for United at this dreadful result, Potter’s influence at Brighton should not be underestimated.
He has lost Yves Bissouma and Marc Cucurella for a combined £88m from the side that beat United in May. Director of football Dan Ashworth has also gone. None of Brighton’s summer signings started this match.
But they moved the ball with a purpose absent from United, while Welbeck was a particular threat against his old club.
Gross and Trossard were both superb and, even without Bissouma, Brighton controlled midfield to ensure United were not able to turn their industry into something more tangible.
Little wonder the jubilant visiting fans chanted “can we play you every week?”.
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Brighton & Hove Albion
- 1de Gea
- 5MaguireBooked at 53mins
- 6MartínezBooked at 45mins
- 23ShawBooked at 74minsSubstituted forMalaciaat 90′minutes
- 39McTominayBooked at 25minsSubstituted forvan de Beekat 78′minutes
- 17FredSubstituted forCristiano Ronaldoat 53′minutes
- 8Bruno FernandesSubstituted forGarnachoat 90′minutes
- 25SanchoSubstituted forElangaat 90′minutes
- 7Cristiano Ronaldo
- 34van de Beek
- 10Mac Allister
- 11TrossardBooked at 53minsSubstituted forLampteyat 75′minutes
- 7MarchSubstituted forColwillat 90+1′minutes
- 14LallanaSubstituted forMwepuat 76′minutes
- 18WelbeckSubstituted forUndavat 90+5′minutes
- 29van Hecke
- Paul Tierney
Match ends, Manchester United 1, Brighton and Hove Albion 2.
Second Half ends, Manchester United 1, Brighton and Hove Albion 2.
Lisandro Martínez (Manchester United) wins a free kick in the defensive half.
Foul by Deniz Undav (Brighton and Hove Albion).
Substitution, Brighton and Hove Albion. Deniz Undav replaces Danny Welbeck.
Offside, Manchester United. Lisandro Martínez tries a through ball, but Anthony Elanga is caught offside.
Foul by Tyrell Malacia (Manchester United).
Tariq Lamptey (Brighton and Hove Albion) wins a free kick on the right wing.
Substitution, Brighton and Hove Albion. Levi Colwill replaces Solly March.
Substitution, Manchester United. Tyrell Malacia replaces Luke Shaw.
Substitution, Manchester United. Alejandro Garnacho replaces Bruno Fernandes.
Substitution, Manchester United. Anthony Elanga replaces Jadon Sancho.
Attempt blocked. Lisandro Martínez (Manchester United) left footed shot from a difficult angle on the left is blocked.
Attempt blocked. Lisandro Martínez (Manchester United) header from the left side of the box is blocked. Assisted by Christian Eriksen with a cross.
Corner, Manchester United. Conceded by Adam Webster.
Attempt blocked. Cristiano Ronaldo (Manchester United) right footed shot from the centre of the box is blocked. Assisted by Jadon Sancho.
Attempt blocked. Christian Eriksen (Manchester United) right footed shot from outside the box is blocked. Assisted by Cristiano Ronaldo.
Bruno Fernandes (Manchester United) wins a free kick in the defensive half.
Foul by Tariq Lamptey (Brighton and Hove Albion).
Attempt missed. Alexis Mac Allister (Brighton and Hove Albion) right footed shot from outside the box misses to the right. Assisted by Enock Mwepu.
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