Manchester United came from behind to beat Leicester City and reach the fifth round of the FA Cup in the process.

Ruud van Nistelrooy, on his first return to Old Trafford since leaving in November following the appointment of Ruben Amorim, was seconds away from taking his former club into extra-time only for ex-Leicester defender Harry Maguire to break hearts with a controversial injury time winner.

The big Man United team news was a debut for January signing Patrick Dorgu as he replaced the injured Lisandro Martinez in the lineup, whilst Rasmus Hojlund was restored in attack after Ruben Amorim opted to start without a recognised striker in the defeat to Crystal Palace last weekend.

However, it was the visitors who settled quicker with Jordan Ayew forcing a routine save from Andre Onana, whilst Luke Thomas was causing problems with his delivery from open play and the odd set-piece.

Leicester took the lead three minutes before the break after Bobby De Cordova-Reid reacted quickest to Wilfred Ndidi’s shot being saved by Onana to head the ball over the Man Utd goalkeeper and into the back of the net.

That goal left many inside the stadium stunned, and there were a few boos from the Old Trafford faithful at half-time, perhaps in response to a first-half where the hosts failed to muster a shot on target.

Amorim’s response to that was a substitution. Dorgu’s debut lasted just 45 minutes as he was replaced by Alejandro Garnacho.

The winger came agonisingly close to an equaliser just after the hour mark as he raced through and dinked the ball over Mads Hermansen only to see Caleb Okoli miraculously get a touch to divert the effort onto the crossbar and then into the goalkeeper’s arms.

Moments later, United were level. Garnacho was at the heart of the move but it was finished off by another substitute as Joshua Zirzkee made no mistake from close range after the ball had fallen in his path when Hojlund’s effort was blocked.

With extra-time looming, Maguire - who did look in an offside position before Fernandes took the free-kick - headed home in injury time to ensure the holders remain on course to retain the FA Cup.