This competition may be somewhere down Mikel Arteta’s priority list but that doesn’t mean the Arsenal manager doesn’t value it. On a night when the fourth-choice goalkeeper Jack Porter became the youngest player to start a game for Arsenal, at the age of just 16 years and 72 days, in the absence of the injured David Raya, it was Ethan Nwaneri who caught the eye as the 17‑year‑old scored twice on his full debut.

After the fallout from their tempestuous draw against Manchester City, Arsenal never really looked like being turned over against opponents who used to revel in giving Arsène Wenger’s sides a bloody nose back in the days of Sam Allardyce, as soon as Declan Rice had put them in front.

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Aaron Collins ensured Bolton did manage to make a contest of it after Nwaneri’s strikes either side of half-time. Arsenal have lifted this trophy only twice and not since the days of George Graham back in 1993, but Raheem Sterling ensured it was a mixture of youth and experience that smoothed their progress into the fourth round against Preston with a goal on his full debut before Kai Havertz, on as a substitute, added a fifth.

Arteta had warned that the effects of the bruising game against City on Sunday would force him to make several changes, with Porter surpassing the record held by Cesc Fàbregas in a League Cup tie in 2003 – a thigh injury keeping Raya out and the back‑up goalkeeper Neto being cup‑tied. Arteta revealed afterwards that the Spaniard is a doubt for the Premier League meeting with Leicester on Saturday but was delighted to see Porter – who was on the bench at Atalanta last week and has excelled for England’s age‑group sides – impress along with a number of other promising youngsters who were not even born when the Emirates Stadium opened in 2006.

“I think he reacted really well and what a way to break a record,” Arteta said. “We gave an opportunity to quite a few academy players and it’s just so fulfilling to see their faces and how much it means to them.”

Bolton have made a slow start after coming so close to being promoted from League One last season but arrived in north London buoyed by a 5-2 thrashing of Reading on Saturday. Ian Evatt, the manager, resisted the urge to select the striker Dion Charles after his hat-trick in that game and made seven changes. Backed by a travelling contingent of 4,000 fans, it was the visitors who enjoyed the more impressive start. Riccardo Calafiori gave the ball away on the edge of his own area and was almost made to pay when John McAtee picked out Scott Arfield with a clever backheel. But he could only fire over Porter’s bar from close range.

Bolton’s fans were incensed when they felt Gabriel Jesus had brought down Josh Sheehan inside the area after another promising attack. They were made to pay soon after when Arfield totally missed the ball as he attempted to clear a cross from Josh Nichols and Rice curled home from the edge of the area. Nwaneri – who set the record as Arsenal’s youngest player in 2022 when he also broke the Premier League mark aged 15 years and 181 days – excelled in the No 10 role as Arsenal assumed control of proceedings, with both Sterling and Bukayo Saka coming close to setting up Jesus on more than one occasion.

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Nwaneri’s first big moment arrived not long before the break when Myles Lewis-Skelly’s pass allowed Sterling to pick out the 17-year-old with a perfect low cross for a simple finish to make it 2-0. It could have been even worse for Bolton had Luke Southwood not been able to push Sterling’s curling effort away to safety or Jesus not fired wide.

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In north London for the first time since a League Cup defeat here in 2011 in the same season they were relegated from the Premier League, Bolton were the architects of their own downfall for Nwaneri’s second. Barely four minutes of the second half had elapsed when they were caught trying to play out from the back and Rice pounced, with Nwaneri coolly applying the finish. “He really feels part of us. He’s playing with that confidence and belief,” Arteta said of his emerging star.

Bolton refused to throw in the towel and Collins pulled one back almost straight away when he capitalised on McAtee’s through ball to round Porter. Their resistance was ended when Sterling poked home after Saka’s shot had been saved by Southwood. The England forward could easily have extended his tally but it was left to Havertz to round off an almost perfect night for Arteta after Sterling’s shot had been saved.