Manchester City had to come from behind to book their place in the FA Cup fifth round on Saturday afternoon as they knocked out League One side Leyton Orient.

Stefan Ortega's own goal, albeit unfortunate after a wonder-strike from Jamie Donely, put Orient 1-0 up after a spirited display. However, Abdukodir Khusanov's first goal for the club levelled the scoring before Kevin De Bruyne scored the winner.

City were made to work for the win in the latter stages of the contest with the EFL side coming close on two occasions in the final 10 minutes. However, Pep Guardiola's men hung on to progress.

READ MORE: 'A pity' - Pep Guardiola gives Nico Gonzalez injury update after Man City debut

READ MORE: What Savinho and Ruben Dias did in FA Cup shows sobering Man City truth

During the game, new signing Omar Marmoush was hacked down from a Brandon Cooper challenge that left City furious. The defender came from behind to take the forward down inside Orient's half.

Referee Darren Bond booked Cooper but there were calls from supporters inside the ground and on social media to send the defender off. However, with no video assistant referee in place, Bond's decision could not be overturned and so the on-field decision stood and he was not sent off.

Speaking on BBC's coverage of the game, former Arsenal defender Martin Keown said of the incident: "I don't like to say it because people talk about professional fouls but you see one there. I wonder if VAR might have looked at that because it's right down his calf."

VAR is not in use for the third and fourth round of the FA Cup, regardless of the locations and teams competing. It does, however, get used in the fifth round and onwards.

The challenge and decision came after Manchester United's late winner against Leicester City was allowed to stand despite four attackers being in a clear offside position before Harry Maguire scored.

Both Ruud van Nistelrooy and United boss Ruben Amorim admitted the goal shouldn't have stood after a poor decision from the linesman.