The journey from euphoria to desolation took 193 seconds for Ipswich. Wild jubilation rolled down all three tiers of the away section at the Etihad Stadium when Sammie Szmodics put the newcomers ahead at the champions, Manchester City. Back in the big time after 22 years. And then it was gone: the ecstasy, the hope and the game. Brutal, this Premier League business.

It can be a bad idea to aggravate the best team in the land but, for a fleeting moment, Ipswich fans could lose themselves in a goal that maintained their phenomenal rise under Kieran McKenna. Szmodics, on his first Premier League start after a £9m move from Blackburn, stole in behind a square City defence and steered Ben Johnson’s pass beyond Ederson.

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Seven minutes had elapsed. They led until the 12th yet were 3-1 down by the 16th, when Erling Haaland converted his second en route to the 10th hat-trick of his City career. McKenna, his players and the fans who had been cavorting 193 seconds earlier were shocked.

The fixture schedule had handed Ipswich a brutal introduction to life back in the Premier League: Liverpool on day one and now this, a crash course in the power of Pep Guardiola’s team and their ability to punish any mistake. There may be consolation in the realisation it can get easier along with their refusal to fold completely.

“It was a fantastic start,” said McKenna. “Then the game was lost in a five-minute spell. There are big lessons to learn but we’ve taken a lot from the first two games. We are in an adaptation process with players who have come from League One in a short space of time. I’m sure we will improve.”

City were too strong, too cool and too experienced to let the shock of Ipswich’s early lead affect them. By the same token, all three of their rapid-fire goals stemmed from Ipswich errors with Arijanet Muric, a one-time City goalkeeper, enduring a debut to forget for the visitors.

Haaland converted emphatically from the penalty spot after Leif Davis committed a needless foul on Savinho two minutes after Szmodics’s shock breakthrough. There was a lengthy delay while the referee, Michael Salisbury, studied the pitchside monitor, having initially dismissed the winger’s penalty appeal. But once the Norway international equalised a sense of order – and the inevitable – was restored.

Kevin De Bruyne soon steered the champions ahead when Muric was caught dawdling in possession on the edge of his area by Savinho, the recent signing from Troyes who resembles Riyad Mahrez in running style, technique and delivery – not to mention he wears the Algerian’s No 26 shirt.

The Brazilian turned the ball back for the City captain to side-foot into an unguarded net. Muric has previous for such mistakes. The Kosovo international did not maintain composure after this one.

Seconds later De Bruyne clipped a ball from just inside the home half between Ipswich’s central defence. Muric came careering towards the edge of his area and Haaland, first to the Belgian’s invitation, simply headed the ball beyond the advancing keeper before cushioning a finish home.

Rico Lewis and De Bruyne struck the crossbar with Muric stranded and Ipswich trying to comprehend what had happened to them, the former from close range, the latter from 30 yards, while Savinho was fortunate to escape conceding a penalty for a foul on Davis.

“It’s really hard to understand how that wasn’t given, especially after the intervention for their first goal,” McKenna said.

Ipswich showed promise on the front foot with the former City striker Liam Delap a handful. But there was never any prospect of a recovery. Muric saved superbly from a Haaland header in the second half but the goal machine would not be denied his hat-trick.

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After a spot of pinball outside the visitors’ box, Haaland arrowed a shot just inside the keeper’s left-hand post for his 94th goal in 101 appearances for City.

“The numbers are ridiculous,” said Guardiola, who introduced Ilkay Gündogan to a rousing reception late on. “He can compete in terms of goals with Cristiano and Messi. Last season he was tired and drained but this season, with no Euros and a rest, he arrived really well.”