Manchester City have blasted their way to the top of the Premier League and only an exceptional team will be able to challenge them. Watford, watched by Elton John and unbeaten before Pep Guardiola’s men rocked up here, fancied their chances but were blown away by a three-goal salvo before half-time.

City did not relent and struck the same number again in the second half, bringing their tally to 15 goals from their past three matches, this demonstration of their attacking power coming after the demolitions of Liverpool and Feyenoord.

City settled the contest in the first half thanks to a three-goal salvo in 10 minutes. Sergio Agüero scored twice and created one for Gabriel Jesus. Nicolás Otamendi added a fourth after the interval with a close-range header. Then Agüero rounded off his hat-trick, which is why he was happy to let Raheem Sterling take the penalty when the winger was fouled a minute from time. Sterling expressed his gratitude by finishing with the ruthlessness he sometimes lacks.

Watford had come into the game on the back of three successive clean sheets in the Premier League but with their first-choice centre-backs still out injured extending that sequence to four was always going to be a tall order against one of Europe’s most awesome attacking forces.

Guardiola made one alteration to the City lineup that had started the midweek dismantling of Feyenoord in the Champions League, with Sterling replacing Bernardo Silva. It took him 20 seconds to make an impact as Sterling skittered down the right and delivered a low cross to David Silva. Adrian Mariappa blocked the Spaniard’s close-range shot, but the storm was never going to abate.

David Silva and Kevin De Bruyne orchestrated City’s relentless assaults. Benjamin Mendy thrashed a 20-yard shot just over the bar before, in the 10th minute, David Silva swept a diagonal pass over to De Bruyne, who cushioned the ball into the path of Sterling. However, the England winger mis-hit his shot from 10 yards. That was the only stain on an otherwise sparkling display by Sterling.

De Bruyne and Agüero went close with shots from outside the area as Watford were corralled deep into their own half. Yet in the 24th minute the hosts almost took a surprise lead from their first venture forward, Richarlison meeting a free-kick by José Holebas and heading a yard wide.

Agüero soon showed the Brazilian how it should be done. In the 27th minute, after Tom Cleverley was penalised near halfway for a foul on John Stones, De Bruyne flighted in the free-kick and Agüero headed past Heurelho Gomes, much to the annoyance of Marco Silva, the Watford manager appealing vigorously for offside.

Gabriel Jesus scores his side’s third goal past the Watford goalkeeper Heurelho Gomes. Photograph: Dan Mullan/Getty Images

The rain was hurtling down and the sky soon fell in on Watford. Agüero scored his second four minutes later, tapping into the net from four yards after excellent work on the left by Jesus and a feeble attempt by Gomes to cut out David Silva’s cross.

Agüero then became the supplier, running at Watford’s frazzled defence before slipping a pass through to Jesus, who fired into the bottom corner of the net from 10 yards.

Watford were inferior, no doubt about that, but never submissive. They rebelled quite strongly at the start of the second half and even had Ederson in the City goal worried for a moment, André Carrillo cracking a fine volley a couple of yards wide from the right-hand corner of the box.

Then Agüero resumed his quest for his hat-trick, twice shooting wide after being fed by Mendy. On the hour the Argentinian was thwarted by Gomes, who batted a crisp shot over the bar. The resultant corner led to City’s fourth goal, Otamendi heading home a cross by David Silva.

Nine minutes from time Agüero finally completed his treble. And with brio, too. After a fine run and pass by Kyle Walker, the striker burst past Christian Kabasele and guided a low shot beyond the reach of the advancing Gomes.

Another tricky run by Sterling provoked a foul in the box in the 89th minute. The winger picked himself up, consulted with Agüero and rifled the ball into the net from the penalty spot.

City, then, surpassed the 5-0 defeat they inflicted on Walter Mazzarri’s Watford back in May. Under Silva they are much better and went into this game knowing that a win would send them to the top of English football for the first time since 1982-83. Graham Taylor’s team finished that campaign as runners-up. City were relegated. That part of the history is certainly not going to be repeated any time soon.