The mission was simple for Chelsea: secure victory against fourth-tier opposition, pump up the confidence of the reserves and maintain this period of rare happiness at Stamford Bridge. It was done quickly, with Christopher Nkunku scoring twice inside the first 15 minutes to set up an easy evening against Barrow.

Nkunku was the main actor, his hat-trick – and Chelsea’s fifth goal – delivered an hour later. But the host forward line all had moments of sparkle. João Félix showed imagination behind Nkunku, Mykhailo Mudryk was electric down the left and Pedro Neto, on the right, scored his first for the club.

It was all too much for Barrow, though their supporters remained in healthy voice for much of the encounter, reminding everyone what this occasion meant to a club who returned to the Football League in 2020 after 48 years away.

“I’ve never seen anything like it,” said Stephen Clemence, Barrow’s head coach. “To be 3-0 down at half‑time, 4-0 and 5-0, and they did not stop singing. Barrow is a long, long way away, I don’t know if you’ve ever been there. But to come down on a Tuesday night – and some are going to get back at five, six, seven in the morning on the coaches – is phenomenal. The town have really got behind us with this fixture. It was very moving.”

Chelsea entered this fixture feeling tranquil, this highly comical club suddenly looking a bit more serious under Enzo Maresca, unbeaten in the league since their opening‑weekend defeat by Manchester City. As expected, they showed off their healthy stockpile of early 20-something weaponry, bringing in an entirely new XI for the visit of the League Two leaders. The out-of-favour Ben Chilwell, Champions League winner at this club in 2021 – made the bench.

Reality came quickly and with cute directness. Félix found room in a midfield pocket and scooped the ball over the visiting backline for Nkunku to latch on to inside the area. The eyes remained on the ball as it dropped for the first-time sidefooted finish past Paul Farman. It had taken just eight minutes.

For Nkunku the cups are where he must make his case to Maresca, the bench his current home in the league. Here he was hyperactive in his showmanship, fancy one-touch play to go with the goals, his second arriving not long after the first. It was the product of some fine work down the right-hand side, Neto making room for Malo Gusto to overlap and send in a ball towards the near post. Nkunku arrived for the backflick to set up the chase for a hat-trick.

Misfortune befell Farman, the Barrow captain, just before the half‑hour. Félix’s free-kick from central shooting range rattled the post before deflecting off Farman into the net for an own goal. Clemence continued to direct as his men ran hard, ensuring no more damage followed in the half.

Yet the carnage continued quickly after play resumed, any half-time wisdom from Clemence lost to the blue wave that engulfed the Barrow goal. Nkunku was a central figure again, taking in a bouncing ball the visitors could not clear before playing in Mudryk, advancing down the wing. The Ukrainian squared for Neto, who did his bit for nominative determinism.

Barrow threatened to reward their faithful. Farman made a couple of fine saves – a one-hander to deny Kiernan Dewsbury-Hall was the standout – and Kian Spence tested Filip Jörgensen with his free-kick prowess. There was a moment of pinball chaos in the Chelsea box from a corner, but no one was able to smash home a consolation.

Chelsea offered no hints of imploding as Maresca rolled on the substitutes, providing them with some precious playing time. Chilwell was sent on at half-time – a pre-planned change, Maresca said – and was given plenty of love from the home support. “He showed that he’s there, he’s ready, he’s working well,” the Chelsea head coach said. “If we have [the] chance, we can give him some more minutes in games.”

Nkunku’s third was his own creation. He hassled poor Farman – who was trying to make room to clear from his area – before dispossessing the goalkeeper to slot into an empty net. Maresca gave a nod to theatricality, immediately calling for the striker to be subbed off, to take in a thunderous ovation, his first hat-trick for the club both clinical and creative. Off Nkunku walked, this firmly his night.