Manchester United set up a FA Cup semi-final against Brighton in remarkable fashion as Fulham captain Aleksandar Mitrovic was sent off for pushing the referee in a 3-1 defeat at Old Trafford on Sunday.

Mitrovic was shown one of three Fulham red cards in a matter of seconds as he barged into Chris Kavanagh for awarding United a penalty after a VAR review for Willian's handball on the line.

The Brazilian was also dismissed, along with Fulham manager Marco Silva on the touchline.

United took advantage as two goals from Bruno Fernandes and Marcel Sabitzer's first for the club kept Erik ten Hag's men on course for a treble of cup competitions.

The Cottagers had been on course to reach the last four for the first time in 21 years when Mitrovic fired them ahead early in the second half.

United needed goalkeeper David de Gea to make a remarkable save to deny the Serbian a second before the tie completely turned on one incident 18 minutes from time.

Willian used his hand to deflect Jadon Sancho's shot behind, preventing a certain goal.

Kavanagh initially only gave a corner, but reversed his decision on seeing the replay to spark chaotic scenes.

Silva was first to be shown red for approaching the official near the VAR monitor.

Willian was then dismissed, but it is Mitrovic who faces the most severe ban after pushing the referee on the arm and then squaring up to Kavanagh.

Fernandes coolly sent Bernd Leno the wrong way from the penalty spot to level.

United quickly made the most of the two-man advantage as Luke Shaw crossed for Sabitzer to flick home.

Fernandes inflicted the final blow as he blasted home in the sixth minute of added time to take United to Wembley on April 23.

- Brighton too good for Grimsby -

Earlier, Brighton dashed League Two Grimsby's dreams of a trip to Wembley with a 5-0 thrashing.

Fourth-tier Grimsby had made history on their way to the quarter-finals by beating five sides from higher divisions.

But Paul Hirst's men were caught out by the class of in-form Brighton, who are eyeing the club's first ever major trophy.

The floodgates threatened to open when Deniz Undav scored for the Seagulls after just six minutes.

Grimsby held out to limit the damage before half-time, but ran out of steam in the second half.

Evan Ferguson scored twice and had another strike ruled out by VAR check for offside.

Brighton's free-scoring wingers Solly March and Kaoru Mitoma then rubbed salt into Grimsby wounds by scoring in the final 10 minutes.

- Doyle stunner sets up City clash -

Sheffield United will face Manchester City in the other semi-final after a City loanee Tommy Doyle scored a stunning stoppage time winner to beat Blackburn 3-2.

The Blades lead Blackburn by nine points in the battle to secure an automatic promotion place to the Premier League next season.

But it was Rovers who won the previous meeting between the sides two weeks ago and the visitors twice led at Bramall Lane.

Ben Brereton Diaz slotted home from the penalty spot after Sam Gallagher's shot hit the outstretched arm of Jack Robinson.

The lead was short-lived as Gallagher deflected Max Lowe's long range effort into his own goal on 27 minutes.

Sam Szmodics restored Blackburn's lead with a cool finish on the hour.

But Oli McBurnie fired in from a narrow angle nine minutes from time before Doyle smashed home a long range effort into the top corner.

City booked their place in the semi-finals on Saturday as Pep Guardiola's men smashed Championship leaders Burnley 6-0.

Erling Haaland scored his sixth hat-trick of the season and second in five days as City remained in the hunt for a treble of trophies.