Liam Delap gave Manchester City a tantalising glimpse of their future before the EFL Cup holders were forced to scrap for a 2-1 victory over Bournemouth in round three.
Delap, the 17-year-old son of former Stoke City favourite Rory, has sparked plenty of excitable talk through his explosive performances for City's youth teams and he wasted little time when it came to making an impression on his senior debut.
Pace, power and a dead-eyed finish in the 18th minute had Pep Guardiola celebrating with delight, but the City boss soon had a furrowed brow as Sam Surridge brought the Championship side level.
Flimsy defending and a failure to create regular clear chances saw Guardiola send for the cavalry in Kevin De Bruyne and Raheem Sterling, with the winner arriving in fortuitous fashion when Phil Foden scuffed a shot into the turf and in after Riyad Mahrez's drive came back off the post.
Foden was one of three players retained from the City side that beat Wolves 3-1 in their Premier League opener and the England midfielder slipped a cute pass to Mahrez in the 16th minute, Bournemouth goalkeeper Mark Travers saving at his near post.
Foden was the provider again two minutes later, with Delap powering past Jack Simpson and clipping a brilliant left-footed finish into the top corner.
City's other debutant, Zack Steffen, was picking the ball out of his net as Bournemouth found a swift, well-worked equaliser - Surridge firing a low shot across the United States international.
The hosts resumed with renewed purpose, Mahrez going close, but Bournemouth continued to threaten a disjointed defence on the counter-attack.
Surridge twice broke through - a combination of Taylor Harwood-Bellis and Eric Garcia, then a wildly sliding Steffen denying him.
Guardiola had seemingly seen enough and sent on De Bruyne and Sterling in place of holding midfielders Rodri and Tommy Doyle after the hour.
But it was Foden who decisively showed his poaching instincts 15 minutes from time.
Surridge could have sent the tie to penalties but glanced wastefully wide in the 87th minute.
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A Wembley winner in this competition in 2018, 2019 and earlier this year, Guardiola showed he was not ready to loosen his grip on the three-handled trophy when he introduced his star attackers to help a youthful starting line-up that had allowed the game to drift. The sight of De Bruyne prone on the turf in stoppage time - the PFA Player of the Year eventually got up, groggy but fit to continue after a collision with Lewis Cook's elbow - showed the cost the City boss was willing to incur.
Delap passes the audition
Sergio Aguero's knee injury and City being thwarted in their ambitions to sign a certain other Argentina international means there are opportunities to be had in the centre of their attack. Delap has burst onto the scene with considerably hype and the combination of athleticism and supreme technique put forth by his goal suggested it is worth believing. The teenager's physical readiness for men's football was just as eye-catching as he flung himself into seven duels, even though a yellow card for a shuddering second-half hit on Travers was absolutely merited.
Nightmare bow for Bernabe
A playmaker by trade, Adrian Bernabe was granted a full debut having appeared as a substitute in the EFL Cup four times over the past two seasons. The 19-year-old's experience could not have been more contrasting to Delap's as he struggled in the unfamiliar position of left-back. Bernabe managed a team-high four tackles but completed only 30 of his 37 passes and was culpable on Surridge's goal before leaving on a stretcher with a serious-looking injury before half-time.
Guardiola's side entertain in-form Leicester City at the Etihad Stadium on Sunday, while Bournemouth return to Championship action against Norwich, who also dropped down from the Premier League last season.