Graham Potter's men finished an impressive ninth last season but have lost influential midfielder Yves Bissouma, who joined Antonio Conte's Tottenham for £30m earlier this window.
Marc Cucurella also departed as he joined Chelsea last Thursday in a £60m switch. It's a huge blow for Potter
Erik ten Hag will get his first feel of Premier League football at Old Trafford today. His pre-season has largely been dominated by the future of Cristiano Ronaldo. His star striker is however expected to feature at some stage today, due to an injury to his teammate Anthony Martial.
Leicester, Brentford, West Ham and champions Manchester City also get their campaigns underway today.
Here, the stats gurus at FiveThirtyEight have predicted how the Premier League will finish – who will stay-up, win the title and seal those all-important European spots
. BRIGHTON, ENGLAND - MAY 07: Leandro Trossard of Brighton & Hove Albion is challenged by Diogo Dalot and Anthony Elanga of Manchester United during the Premier League match between Brighton & Hove Albion and Manchester United at American Express Community Stadium on May 07, 2022 in Brighton, England. (Photo by Mike Hewitt/Getty Images)
Manchester United will start their new Premier League season against Brighton at Old Trafford today Photo: Mike Hewitt
. Manchester City - 85 points
End of season probabilities - Relegation: Photo: Mike Hewitt
. Liverpool - 80 points
End of season probabilities - Relegation: Photo: Andrew Powell
. Chelsea - 72 points
End of season probabilities - Relegation: Photo: Catherine Ivill
. Tottenham Hotspur - 66 points
End of season probabilities - Relegation: Photo: ANDY BUCHANAN
. Arsenal - 61 points
End of season probabilities - Relegation: 2%. Top-four finish: 28%. Premier League title: 2%. Photo: Mike Hewitt
. Man United - 57 points
End of season probabilities - Relegation: 4%. Top-four finish: 18%. Premier League title: 1%. Photo: Ash Donelon
1. Manchester City - 85 points
End of season probabilities - Relegation: Photo: Mike Hewitt
2. Liverpool - 80 points
End of season probabilities - Relegation: Photo: Andrew Powell
3. Chelsea - 72 points
End of season probabilities - Relegation: Photo: Catherine Ivill
4. Tottenham Hotspur - 66 points
End of season probabilities - Relegation: Photo: ANDY BUCHANAN