The visitors made the breakthrough in the first half when Brajan Gruda scored the opening goal, before former United striker Danny Welbeck doubled Brighton's lead.

The 35-year-old marked a familiar return to his old ground by netting Brighton's second, taking his career tally against United to eight goals. It was his sixth strike at Old Trafford against his former club.

United, watched by former manager Sir Alex Ferguson, were being led on an interim basis by Darren Fletcher, Welbeck's old team-mate.

The hosts rallied late on when Benjamin Sesko headed home five minutes from time, but Brighton held firm despite sustained pressure.

Matters worsened for United in the final minute when 18-year-old substitute Shea Lacey was sent off.

"Very proud because I think we had a tough start. We made a lot of changes so they needed a bit of time to get used to each other," Hurzeler told the BBC.

"But then we started playing football after five or ten minutes, that helped us a lot.

"We controlled the game better, we created chances, we scored a nice goal. I think we had a big chance to score a second goal. They were dangerous, and we weren't defending our best in the first half. In the second half we did it better.

"Overall, I was pleased with the performance.

"I'm very happy for the fans because they always give us great support. They have [had] to travel twice to Manchester and it's not the closest place for us. So I'm really happy for them. They spend a lot of money and time for us. Hopefully they have a nice Sunday."

The result was Brighton's first ever FA Cup victory over United, achieved on their seventh attempt, and dumped the 13-time winners out of the competition.

United have now exited both domestic cups at the earliest possible stage, having already been eliminated from the EFL Cup by League Two Grimsby, a feat not seen since the 1981-82 season.

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