It still feels too early, with the leaves falling from the trees and fireworks in the sky, to assume Manchester City are going to turn the Premier League into a procession and that nothing can possibly go wrong for Pep Guardiola’s freewheeling side. But it certainly seems a possibility when they are playing this way, the goals are flying in from every angle and the team enjoying the view from the top of the league are on course to smash just about every scoring record in history.

From their first 11 fixtures City have greedily accumulated 38 goals. Their goals-per-game ratio actually came down a touch here but, once again, it was difficult to tot up how many chances they created and, in the process, they made it another demoralising experience for Arsène Wenger’s side. This is the first time since 1981 Arsenal have lost four of their first six away games. The defeat leaves them sixth, 12 points from the top, and it would have been a rout had the home team been more ruthless during their periods of near-complete superiority.

As it was, City made do with a goal each for Kevin De Bruyne and the substitute Gabriel Jesus and, in between, a penalty for Sergio Agüero on the day the Argentinian was presented with a “Blue Boot” trophy for becoming the club’s all-time record scorer. Shaun Goater, Niall Quinn and David White were among the lineup of former City forwards at the pre‑match presentation and it was another reminder how this club has changed under Abu Dhabi ownership.

The scariest part for the chasing pack of teams is that Guardiola’s men might actually regard this as a slightly scruffy performance at times. There was even the sight of David Silva, Fernandino and De Bruyne misplacing a few passes and Raheem Sterling might wake in a cold sweat when he thinks back to a two-on-one breakaway in the first half when his mind filled with uncertainty and he made a pig’s ear of his pass to Leroy Sané. Guardiola, scarcely believing what he had just seen, looked close to the point of spontaneous combustion.

Ultimately, though, City were the better side by some distance and there was only one brief spell, after the Arsenal substitute Alexandre Lacazette had made it 2-1, when the home side had a period of vulnerability. By the end there were olés from the crowd, shortly after the announcement that the brilliant, mesmeric De Bruyne had been named as the game’s outstanding performer. Those olés are becoming the soundtrack to what is shaping up to be a record-breaking season. “Can anyone stop them?” Wenger asked afterwards. “It will be difficult this season.”

Wenger could not resist a spiky follow-up line about the standard of refereeing – “If they get decisions like that, at home, they will be unstoppable” – and was entitled to complain that City’s third goal was offside. Yet Arsenal look what they are: a side that has been drifting for too long, 13 years and counting since their last league title. “He wants to be blue,” the home fans sang about Alexis Sánchez and Wenger could not deny it. It was, he said, a “huge mental test” for Sánchez to face the team he nearly joined in the last transfer window.

Play Video 1:18 Wenger bemoans referee after Manchester City outclass Arsenal – video

Sánchez had a difficult afternoon and, on this evidence, he might not find it straightforward getting into City’s starting XI if the transfer is resurrected in January. Francis Coquelin looked out of place as an experimental centre-half in a 3-4-2-1 formation and it was not until Agüero’s penalty that Lacazette came on to score with a right-foot finish, set up by Aaron Ramsey, to raise the possibility of an Arsenal comeback.

Instead back came City, swarming all over their opponents before Jesus turned in Silva’s pass while the Arsenal defence waited for offside to be given. The flag should have gone up but it was inches rather than yards – a bad decision, yes, but at this level it was startling to see the collective freeze from the visiting defence.

De Bruyne took his goal beautifully, playing a one-two with Fernandinho before drilling a diagonal left-foot shot past Petr Cech. But that, too, was aided by the reluctance of every single Arsenal player, most notably Laurent Koscielny, to make a tackle or close the Belgian down.

Wenger was unhappy about the penalty and claimed the standard of refereeing in the top division is going down year after year. These outbursts are nothing new after Arsenal defeats and, whatever Wenger might believe, the referee, Michael Oliver, was entitled to think Nacho Monreal had bundled Sterling over. It was debatable but most referees would have concluded it was a foul and Wenger, almost certainly, would have if it was the other way round. Agüero’s penalty went in off the post and, as City power on, Arsenal are becoming a speck in the distance.