Pep Guardiola was never going to let Nico O’Reilly leave quietly. As the Manchester City players applauded their travelling supporters, Guardiola gave his 20-year-old match-winner a little shove in the back, pushing him in front of the fans who sang his name.

O’Reilly is becoming used to FA Cup accolades this season, having scored a brace in the last round against Plymouth and another strike in the 8-0 rout versus Salford but here, on the south coast against Bournemouth, it was his instant impact that dragged Guardiola’s side into a seventh successive semi-final.

He was on the pitch barely three minutes, coming on at half-time at left back, when he surged forward into the channel to collect Kevin De Bruyne’s pass and swung a teasing, curling cross to the back post for Erling Haaland to tap in the equaliser, before he set up Omar Marmoush for the winner with a fine piece of skill.

Guardiola knows that if he is to rebuild his City dynasty beyond this season, get them back to the summit of English football again, it will be the young blood that has to inspire it.

He spoke after the match about how his legendary City players, those that have won six Premier League titles in seven years and now reached seven FA Cup semi-finals in a row, have struggled to maintain the ‘heart and desire’ to go again and again – even if they did so in the end at the Vitality Stadium.

Pep Guardiola pictured (right) with Nico O’Reilly after Manchester City’s win at Bournemouth

Manager Guardiola pushed O’Reilly forward so he could soak up the adoration of the away fans

O’Reilly produced two assists on Sunday as City came from behind to win on the South Coast

For too long now, his heroes have seemed mortal. They no longer hold that same aura, the sense that they are untouchable and exist on another, unearthly plane. ‘Before, teams were more cautious,’ said Guardiola recently of his opponents. ‘Now, teams are so brave.’

The likes of De Bruyne, Ilkay Gundogan and Bernardo Silva have got older and slower. They still have the quality to pick the perfect pass when it matters but those high-energy, high-pressing up-and-comers like Bournemouth can swarm them. They did it here back in November in a victory that Guardiola acknowledged was the game that started their slide into mortality.

Before O’Reilly’s introduction, it looked to be happening again.

After just five minutes, Silva brought down a chipped pass but before he could get the ball out of his feet, Antoine Semenyo shrugged him off it. Silva remonstrated with the referee as if it were an affront that opponents are permitted to show such disregard for legacy and prestige.

Matheus Nunes did the same later when he, also flattened by Semenyo, took so long to get up again that De Bruyne waved across the pitch to implore him to get on with it.

The only thing Nunes got on with was gifting the ball to Bournemouth outside the City penalty area and in the space of a few passes Evanilson had it in the net and the Cherries were in front.

It was the 21st time Man City had conceded the first goal in a game this season. The only other Premier League clubs to do so more are relegation fodder Leicester City and Southampton as well as famously useless Manchester United.

All Guardiola’s big names were there, and all were faltering again. Haaland could have had a six-minute hat-trick but headed wide from close range, put a penalty straight at Kepa and then chipped a one-on-one over the bar. At the other end, Ederson’s usually top-class distribution took on the guise of a rebellious garden sprinkler.

Sunday’s 2-1 win saw City reach the semi-finals of the FA Cup for a seventh season in a row

Manchester lad O’Reilly, 20, has now featured in nine first-team games for City this season

Ruben Dias played a loose pass for Gundogan and threw his arms up in frustration.

Then O’Reilly came on and it all changed. There was the heart to burst forward into the space to receive the ball from De Bruyne for the equaliser. There was the desire to pounce on Semenyo’s mistake to win the ball and set up the winner.

While he might be part of the new wave of City talents coming through, there’s still something quintessentially Guardiola about how O’Reilly is being used – he’s not actually a left-back. Of course he’s not.

‘We cannot forget he is a No 10,’ said Guardiola after the match. ‘But he has pace, he is so intelligent, has quality with the ball in the final third, he has vision.’

The technique O’Reilly showed for Marmoush’s winner, to control the ball, turn and play in the pass with the outside of his boot in such a tight space showed those qualities.

He’s played as a central and holding midfielder, too, and at 6ft 2in is a threat at set pieces as well.

Born in Failsworth, just north of Manchester, he grew up as a City fan in a household split between blue and red. He was the best player in City’s under-10s and under-11s as they won back-to-back Premier League national titles.

Back in 2023, he scored a sensational scorpion kick for the under-18s and a week later popped in a 40-yard lob against United. He can set them up and he can score them too.

Chelsea tried to sign him in January but received short shrift and you can see why.

Guardiola joked that O’Reilly has played his way on to the team sheet for Wembley. You imagine it won’t be too long until it is there to stay.

If Pep is to build something special again at City, he can no longer rely solely on the old guard. He will one day need young hearts like O’Reilly to lead the way.