It was a funny old occasion at the King Power Stadium as Claudio Ranieri went from reflecting on where things are going wrong for Leicester City in defence this season to looking forward to “continuing the fairytale” in one of the most historic games in the club’s history. In the middle of it all a photograph of Emile Heskey slid off the wall as a dozen or so television crews jostled for position on a platform that was never built with Champions League press conferences in mind.

For a reminder of how far Leicester have come it is almost eight years ago to the day since the Midlands club, then in League One, hosted Lincoln at the same venue and won on penalties in front of a crowd of 8,046 to reach the Johnstone’s Paint Trophy Northern Section quarter‑finals. Porto’s visit for Leicester’s first Champions League home match has generated rather more interest.

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Yet the spotlight is also shining on Leicester for another reason. The season is only six Premier League matches old but Ranieri’s side have already endured as many defeats (three) as they did in the whole of their title-winning campaign. The champions have also shipped 11 goals across those fixtures, which is as many as Leicester conceded between the end of December and the final game of last season.

Ranieri did not hide his disappointment with the results and Leicester’s defending. “Of course it’s a concern,” the Leicester manager said. “Last season everything was perfect; this season, no – the first chance the opponents have, they score. I’m not happy when my teams don’t react. We can concede a goal, but I want to see us react every time.

“I spoke to them [the players] and I am very sure they understood it all. Of course we can concede a goal, but I want to see my team continue to play.”

The 4-1 defeat at Old Trafford on Saturday was fresh in Ranieri’s mind. Manchester United scored all four goals in what Marc Albrighton described as “a mad 20 minutes where we switched off and lost concentration”.

Three goals came from corners, with a few of the Leicester players suggesting that the clampdown on holding and grappling at set pieces was affecting their defending, with some now afraid to mark too tightly. Ranieri, however, refuses to accept that is the case and made it clear to his squad in a meeting on Sunday that they need to revert to type.

“I spoke to the players and they were scared,” the manager said. “The referees speak about not a new rule, it’s something we’re used to doing. I said: ‘Why change?’ Last season we were one of the best in the league and concede very few goals from set pieces and now we leave four metres [of space]. Now we have to go back to our strength.”

Liverpool also put four past Leicester in the league earlier in the month and for Ranieri it is the way that his team have imploded that has worried him most. “When we concede versus Liverpool or Man United it could be normal for us to lose. But it’s not normal when we lose our way,” the Italian said.

Hosting Porto offers an opportunity to rebuild a bit of confidence and, on the back of Leicester’s impressive 3-0 win against Club Brugge a fortnight ago, take a significant step towards the Champions League knockout stages. The Portuguese club have won Europe’s premier club competition twice, in 1987 and 2004, yet the bigger picture shows that they have lost 14 of their 16 matches on English soil and never tasted victory.

They will also not welcome the sight of Islam Slimani leading the line for the Foxes. Slimani, Leicester’s £29m club‑record signing, has scored five goals in his previous three matches against Porto, all of them in 2016 and the most recent coming in Sporting Lisbon’s 2-1 victory last month.

While Ranieri had no idea that Slimani was known as the “Dragon Slayer” during his time with Sporting – Porto are nicknamed the Dragoes – the Leicester manager knows all about the Algerian’s goalscoring record and said that he had met the striker to discuss their opponents’ qualities. “I spoke with [Slimani] about Porto,” Ranieri said. “He’s scored a lot of goals against Porto and I’m sure he’ll be a threat to them. But we have a lot of respect for Porto, they are a lot more experienced team in Europe and are used to staying at the top of their league.”

For Leicester, being champions is a totally new experience and it was put to Albrighton that the players have found it harder to deal with the level of expectation this season.

“I wouldn’t say that we are feeling the pressure of that,” he said. “We have had a tough start to the Premier League campaign – we’ve played Arsenal, Manchester United and Liverpool. Obviously the manner we have lost is not good, but to say we prefer being underdogs isn’t true.”

Either way, once that Champions League soundtrack starts playing at the King Power Stadium, domestic football will be a long way from anyone’s mind. “It’ll be fantastic for our fans,” Ranieri said. “A lot of them came to Bruges and listened to the music – now a lot of them can listen in Leicester. It’ll be fun to continue the fairytale for them.”