So it is best that you send us a careful picture of the Premier League armband to be sure.

Everything was looking rosy for Leicester, leaving aside the fact that they had been largely outplayed. Fine goals by Ayoze Pérez and Harvey Barnes gave them a two-goal lead over Napoli, their main rivals in Group C and the joint favourites to win the tournament outright. But late goals by the outstanding Victor Osimhen earned a share of the points, which was the least the classy visitors deserved.

Leicester’s frustration deepened when Wilfred Ndidi was sent off in stoppage time for a second bookable offence. Worse followed in the stands after the final whistle when a smattering of home fans clashed with Napoli supporters, with police and stewards breaking up skirmishes while bottles were hurled by people on both sides. Uefa is sure to investigate. Here is a snap judgement: it was a pathetic sight at the end of an exhilarating contest on the pitch.

“I was really pleased with the team in terms of the mentality, the goals we scored and the resilience we showed for a lot of the game,” said the Leicester manager, Brendan Rodgers. “That was real good measure for us, with the experience and quality that Napoli have. The crime isn’t giving away the two goals, the crime is if you don’t learn from it – and I’m sure that is something this young team will do.”

Both these clubs have plenty of quality and might have met in the Champions League this week if they had not dropped out of the top four of their domestic leagues on the last day of last season. Each aims to go far in this competition, even if the Napoli president, Aurelio De Laurentiis, called in the buildup to the game for a revamp of European football to make it “more modern and lucrative”.

Napoli were quick to show their menace at the King Power, with Osimhen testing Kasper Schmeichel in the third minute with a powerful shot from just outside the area.

Leicester wasted no time retorting. Pérez, eager to redeem himself after being sent off against West Ham in his last outing, burst into the right-hand side of the box and showed impressive strength to fend off Kalidou Koulibaly before feeding the forward Patson Daka, who helped the ball on to Barnes at the back post. David Ospina bolted off his line to divert Barnes’s shot just wide from six yards.

Lorenzo Insigne, a victor in that encounter, tried to negate Pérez’s goal in the 13th minute but misdirected his free-kick from the edge of the area. Then Osimhen did likewise after beating Jonny Evans with a nutmeg.

Evans departed injured at half-time, which Leicester were grateful to reach with their lead still intact. The full-back Timothy Castagne blocked a close-range effort from Piotr Zielinski, Insigne blasted wide twice and Schmeichel batted away a dangerous header from Hirving Lozano before the break.

Rodgers, recognising the need to stem the flow, made two substitutions for the second period. But Napoli grew more dominant and Leicester struggled to get out of their own territory in the early part of the second half.

Daka and Iheanacho scampered hard off the ball but seldom got to spend any time with it – until just before the hour, when the Zambian fired into the net after nimble work by Iheanacho and Youri Tielemans. The hosts erupted with joy and relief, only for a VAR review to rule that Daka had been fractionally offside.

But Leicester had the taste for goals again. Five minutes later they got one with which no one could quibble when Barnes lashed a low shot from the left into the far corner after Iheanacho opened up Napoli’s defence.

Still Leicester were not safe, especially not with Osimhen still on the hunt. The striker brought Napoli back into contention by poking the ball over the out-rushing Schmeichel after nifty play by Insigne and Fabián Ruiz.

There was no surprise that the Nigerian was responsible for the final twist, too. When Matteo Politano flighted in an inviting cross from the right, Osimhen leapt above Caglar Soyuncu and nodded into the net from five yards.