City dominated from the off, finding themselves two goals to the good after 20 minutes, thanks to goals from Raheem Sterling and Fernandinho, with half-chances from Kevin De Bruyne and David Silva coming close to a third.
Their dominance continued into the second period, with chances for Nolito, before Michail Antonio somehow got the Hammers back into contest. The result never seemed out of questions, with City continuing to dominate before Sterling added a third in extra-time to round up the three points with ease.
Dominating from the word go
Both these sides have had contrasting starts to their individual campaigns, with the Citizens remaining unbeaten, while Slaven Bilic’s side headed to the Etihad Stadium having crashed out of Europe in midweek.
The Hammers seemingly still had a hangover from their 1-0 defeat to Astra Giurgiu, as they were knocked back by two quick-fire first-half goals.
It took all of seven minutes for City to take the lead and it proved simple enough for Guardiola’s side. Silva did well to pick out Nolito on the right, and it was simple enough for him to find an unmarked Sterling, who stroked home with ease from six yards.
They added to their advantage 11 minutes, and once again the away side’s defence were at fault. De Bruyne produced an excellent free kick into the area, and Fernandinho was allowed to head home easily for his first goal in little under a year.
Despite having a comfortable lead, it didn’t seem that City were going to let up, as they looked to add a third before the break. De Bruyne came the closest, with the Belgian opting to shoot with his set-piece, and it only just rippled the roof of the net.
Pushing for a third
City picked up where they had left off as they came out for the second period, and the majority inside the Etihad thought the points were secured. De Bruyne flicked it to Sergio Aguero, who did well pick out Nolito who had an easy tap-in but both were deemed to be offside.
Nolito came even closer moments later, as another dangerous set-piece from De Bruyne was cleared by Winston Reid, but it was only as far as Nolito but he can only find the side-netting.
Causing an upset?
Bilic will have been very disappointed with his side’s performance, but they somehow managed to find themselves right back in the contest with their first real attack on Willy Cabellero’s goal.
New-signing Arthur Masuaku, produced a decent ball into the area for Antonio, and very similarly to his winning goal against Bournemouth the week previous, he bullied his way to the far post to head in from close-range.
Taking back the reigns
After their minor blip, City took back the reigns of the game as they searched for what would be the Hammer blow, and had many chances to grab a third.
It almost came from a West Ham player in the 70th minute, as a pass from Aguero came off the foot of Sam Byram, but Adrian did well to react to save the potential howler.
A lot had been made in the media about Samir Nasri's fitness, but the Frenchman almost made an excellent point to his new coach. The former Arsenal man found himself one-on-one with Adrian with Spaniard producing a fine save, he looked to turn in the rebound but Byram was on the line to clear the danger.
Signed and sealed
It had been an excellent performance form Guardiola's side, but they weren't through yet as they continued to push for that all important third goal, and were eventually rewarded for their efforts.
Silva came very close in normal time, as he was played through by Nasri and looked to have Adrian beaten, but his effort clattered off the upright.
It was Sterling who wrapped up the victory, tow minutes into extra-time, and it was a spectacular way to finish the contest. He did well to get around Adrian, but the angle from the byline didn't look promising, but he somehow managed to stick it home through the legs of the defender.