It wasn’t vintage City, but given our exertions at Wembley on Sunday, Pep Guardiola will view this as a vital three points in our bid to become the first side in a decade to retain the Premier League title.
City started brightly, creating a flurry of clear-cut chances in the opening few minutes.
Kevin De Bruyne hit a beautiful right-footed effort from distance that looked to have beaten Lukas Fabianski, only for the ball to sail wide of the upright.
Riyad Mahrez should have done better when David Silva picked him out at the back post with a brilliant pass but he put his effort wide from just a few yards out, before Silva hit the post from De Bruyne’s pinpoint ball across the six-yard box.
Three excellent chances and not even five minutes on the clock. The visitors looked rattled.
But the flow of the game soon changed. Usually such an open side, West Ham were playing conservatively, happy to put men behind the ball and frustrate City.
In Declan Rice and Pedro Obiang, the employed two sitting midfielders who shielded a rigid back four. It stifled our play, and although we enjoyed the majority of possession, opportunities were limited for the remainder of the first half.
But the game burst into life in the second period.
West Ham should have gone ahead moments after the restart when Felipe Anderson did superbly to find Andy Carroll at the back post, but his outstretched effort was saved by Ederson in what is the latest example of his brilliance.
It was a scare that sparked City into life, and with Raheem Sterling and Bernardo Silva brought off the bench, there was renewed purpose and vigour in our play.
The breakthrough came just before the hour mark. Bernardo, who West Ham struggled to contain, was adjudged to have been fouled by Anderson inside the area, and Aguero coolly converted from the spot. It was the Argentine's 25th of the season in all competitions and his 18th in the Premier League alone, numbers that further underline his instincts in front of goal.
Fabianski saved brilliantly from Raheem Sterling, before Ryan Fredericks’ last-ditch clearance on the line from Silva's follow up saw West Ham, somehow, remain just a goal behind.
Sterling then saw his long-range effort tipped round the post by Fabianski, before side-footing one wide after more great world from Bernardo.
This wasn't City at our free-flowing best - in fact, it's the first time this season we've failed to score at least two goals in a home league game - but three more points in the bag after Sunday's efforts are very welcome, indeed.
Man of the Match: Sergio Aguero
Another tireless performance and winning goal from City's main man.
118 - Sergio Aguero has had a hand in 118 goals in 119 Premier League appearances at the Etihad (96 goals, 22 assists). Marvel.— OptaJoe (@OptaJoe) February 27, 2019
And a special mention for Bernardo, whose second-half introduction helped turn the match in our favour.
It's becoming increasingly clear this season’s title race is going to the wire.
Liverpool’s comfortable win at home to Watford means the situation remains the same after the midweek fixtures: The Merseysiders are top of the table by a point.
With just 10 games of the season remaining, there’s no room for error.
Welcome home, Pablo
Has there ever been a reception like that for a returning City player?
Pablo Zabaleta’s introduction caused a huge surge of noise, the City fans keen to show their appreciation for a player who served the club immaculately over a nine-year period.
City have now won 14 of 15 Premier League games at the Etihad Stadium this season, a remarkable record.
"We played so well. You see the result 1-0 it looks like it could be better. We create a lot of chances in the first five mins.
"Of course, we didn't score enough goals for the way we played but the way we defend the second balls was incredible. We concede one shot on target. After 120 mins [on Sunday] we made an incredible performance.
"It was really good, believe me. The last 20 mins of first half was flat but not bad. In the mind of the players they start to think about how can it be 0-0 after all the chances we had.
"Raheem and Bernardo help us make a step forward in intensity in the final third. We create a lot of chances. We did well, really. Honestly, i think we play a really good game."
City travel to Bournemouth on Saturday for a rare 3pm kick-off, before Watford visit the Etihad seven days later.