Manchester United kept their trophy hopes alive for this season and ended Liverpool's quest for four trophies with a dramatic extra-time victory in an FA Cup quarter-final classic at Old Trafford.

In an incident-packed encounter, it was substitute Amad Diallo who sent Erik ten Hag's side to Wembley with a strike in the dying seconds of the additional period to send the Stretford End wild, the match-winner then being sent off after getting a second yellow card for his celebrations.

It summed up everything about this thriller, United manager Ten Hag doing a dance of delight as Diallo's shot flashed past Liverpool keeper Caoimhin Kelleher.

United desire for a place in the last four at Wembley was illustrated in a fast start which saw them take an early lead, Scott McTominay bundling home from close range in the 10th minute after Kelleher had pushed out Alejandro Garnacho's shot.

Kelleher denied McTominay again from close range before the tie was turned on its head as Liverpool scored twice in three minutes on the stroke of half-time to take the lead and stun United.

Alexis Mac Allister equalised when his shot was deflected off Kobbie Mainoo, United paying the price for allowing the excellent Jarell Quansah to race forward unchallenged to play in Darwin Nunez.

And Mohamed Salah, the regular scourge of United, struck again swiftly with his 13th goal in 14 appearances against them, turning home in front of the Stretford End after Andre Onana saved from Nunez.

Liverpool had the better of the opportunities after the break but substitute Antony drew United level three minutes from the end of normal time with a low shot on the turn before Marcus Rashford then somehow steering a simple finish wide with the goal at his mercy to win the game.

Substitute Harvey Elliott put Liverpool back in front after 105 minutes, his 20-yard shot taking a crucial touch off substitute Christian Eriksen to swerve tantalisingly out of the reach of Onana.

It looked like the game was up for United but Rashford made amends for his earlier miss with another equaliser to set up that sensational finale with Diallo the central figure.