“We couldn’t, could we?” wrote Michael Flynn, Newport County’s manager, in the match programme. No, ultimately, was the answer but Newport gave it one hell of a go on a day that will live long in the memory for every one of their supporters, in particular that moment when Pádraig Amond pulled a goal back with two minutes remaining and the League Two club dared to dream.

It was 2-1 at that point and there was a flicker of hope that disappeared just as quickly as it arrived. Phil Foden, who was the standout player on a pudding of a pitch, scored the second of his two goals in the 89th minute with a splendid left-footed shot and it was then left to Riyad Mahrez to add a fourth deep in injury time.

Phil Foden ‘brilliant’ for Manchester City against Newport, says Pep Guardiola Read more

In that sense, the scoreline felt a little harsh on Newport, who played with tremendous energy, spirit and belief. They became only the fifth club this season to prevent City from scoring in the first half and could easily have gone into the interval ahead. Tyreeq Bakinson will still be wondering how Ederson managed to get across to superbly claw away his header in the 14th minute after a long throw caused consternation in the City area.

Flynn, who was full of praise for his players afterwards, admitted that those sort of chances have to be taken if something extraordinary is going to happen. The Newport manager would also have needed his goalkeeper to play out of his skin and, unfortunately for Joe Day, who has been so impressive during their FA Cup run, a couple of City’s goals felt a little soft.

Play Video 0:36 Pep Guardiola: Newport were chanting 'Who are you?' It was nice – video

Not that anyone at Newport deserves any criticism. It has been a remarkable run to the fifth round of the FA Cup – the first time the club has reached that stage in 70 years – and they can take great pride from the way in which they eliminated Leicester and Middlesbrough and frustrated Manchester City for so long. Asked how he felt at half-time, when the game was still goalless, Flynn replied: “I was buzzing, especially after watching them last week – they were 4-0 up [against Chelsea] after 25 minutes.”

City turned up a little under an hour and a half before kick-off and it felt slightly surreal to see Guardiola and his players making their way across the Rodney Parade pitch, which was threadbare in places and covered in rugby markings, to get to the dressing rooms at the other end of the stadium. “Who are ya?” chanted the Newport supporters, with not the slightest hint of irony in their voices.

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The team news that followed provided an answer to that question. “Helluva side he’s put out,” said one Newport supporter as he ran his eyes over the household names. Guardiola, clearly, was not taking any chances, even if Newport are 82 places below them on the league ladder and a million miles apart in so many other ways. To put that chasm into some sort of perspective, City’s starting XI cost £320m to assemble. Newport’s was put together for £50,000 and only two of the players commanded a fee.

Not that any of that seemed to bother Newport’s raucous fans. The atmosphere inside Rodney Parade was electric as every tackle and header won by an amber shirt was greeted with huge cheers. Remarkably, the home supporters nearly had much more to celebrate when Bakinson had that opportunity following Mickey Demetriou’s long throw. Guardiola had spoken beforehand about Newport’s threat from set pieces – “They are taller and stronger than us and, in some areas, might be better than us” – yet knowing what is coming and being able to do something about it are two different things.

Facebook Twitter Pinterest Pádraig Amond scores Newport County’s late consolation. Photograph: Tom Jenkins/The Observer

Leroy Sané had come closest to scoring for City in the first half when he hit the crossbar, and it was the German who forced the breakthrough shortly after the restart. After playing a neat one-two with Gabriel Jesus, Sané hammered a powerful left-footed shot that struck Day in the face before looping into the empty net. Day was left with a bloodied nose and Newport were now in the unenviable position of chasing the game.

The Newport keeper then smartly denied Danilo but was left beating the ground in frustration after Foden’s low shot slipped past him. Newport could have been forgiven for wanting to hear the final whistle at that point but, to their immense credit, they refused to give up the fight and were rewarded when Amond capitalised on a mix-up between Aymeric Laporte and Nicolás Otamendi to lob Ederson and maintain his record of scoring in every round of the FA Cup this season.

It was game on – but for no more than a minute. Foden, shifting the ball on to that lovely left foot, thrashed home a splendid shot that nestled in the top corner and then Mahrez, with another rising effort, made it 4-1. City are through to the last eight but Newport felt like winners too. “They’ve just invited our players into their changing room,” added Flynn. “That means a lot for any player, especially from League Two.”