Mason Greenwood put Ole Gunnar Solskjaer’s side ahead early on and Bruno Fernandes doubled the lead on the half-hour mark.
A fantastic counter-attack saw Fernandes smash in another to keep United in the running for a fifth-place finish in the Premier League with a 3-0 win.
Brighton aren’t quite completely safe at the bottom, but won’t worry too much if they bounce back with a better performance next time out.
Here are the player ratings from the Amex Stadium.
Matt Ryan – 5. Easily beaten at the same post for the first two goals.
Martin Montoya – 5. Held his ground but the overlaps beat him and offered nothing going forward.
Lewis Dunk – 5. Not tight enough on at least one of the goals.
Shane Duffy – 5. Not his usual commanding self, couldn’t stop the constant waves of attacks.
Dan Burn – 6. Probably the best of the defensive quartet, but never got close to stopping Greenwood.
Tariq Lamptey – 7. Played further forward than usual and looked decent on the wing. Fierce crosses, plenty of tackles, not afraid to dribble at United.
Davy Propper – 5. Overrun, didn’t help protect the defence and subbed at the break.
Dale Stephens – 5. Similar to Propper but without being subbed early, in truth. Better in the second half but no more effective.
Yves Bissouma – 6. A reasonably formidable barrier on the flank, but definitely better once he had shifted back into the centre of midfield.
Alexis Mac Allister – 7. Got to grips with the physical challenge quickly and showed some neat moments of link-up play despite very little service.
Aaron Connolly – 7. Hard-working, fashioned a few early openings, had good movement off the ball.
David De Gea – 7. Made a couple of good saves in the second half but was mostly untroubled.
Aaron Wan Bissaka – 7. Good runs down the flank to open up a very defensive Brighton side. Claimed an assist for the first goal, defended well when called upon but Brighton didn’t have much width on his side.
Victor Lindelof – 5. One or two early questionable moments and then beaten in the air and on the ground during Brighton’s best spell in the game.
Harry Maguire – 6. Solid in the air but similar to his defensive partner had a couple of issues with decision-making under pressure.
Luke Shaw – 7. Standard performance. Got forward plenty, delivered some nice passes in the final third when United were on the attack.
Paul Pogba – 8. Easily the best player on the park. Great passing range, too powerful for any Brighton opponent, got into clever spaces in the attacking third.
Nemanja Matic – 6. Held his ground in the centre and passed the ball easily.
Mason Greenwood – 8. Tremendous early goal, but arguably his assist on the counter-attack was even more impressive for vision and execution.
Bruno Fernandes – 8. Two goals, another very good display. Bet they wish they’d bought him in the summer instead of January.
Marcus Rashford – 6. Reasonably quiet game on the left. Made some good openings with his runs but on the periphery at times.
Anthony Martial – 7. Not as good a performance as his hat-trick display, but he led the line as well as expected against the massed ranks of the home side.