The Hammers have since bounced back, winning two and drawing one of their next three league games.
They face Aston Villa later tonight and will be hoping to pick up all three points against the newly-promoted side who have lost three of their opening four games.
West Ham boss Manuel Pellegrini will hope to get his tactics right against Dean Smith’s side after admitting he made a mistake while selecting his starting XI for the clash against Man. City.
The Chilean opted for the centre-back pairing of Fabian Balbuena and Issa Diop for the game, but has since dropped the Paraguayan for Angelo Ogbonna.
The Italian has played the last three games alongside the Frenchman, and is expected to start against Villa and continue playin for the time being.
“The reason was that Fabian Balbuena couldn’t work too much in the pre-season. He arrived from his national squad late and he played just one [full] game,” Pellegrini told football.london.
“That was my mistake to play with him in the first game because I trusted too much in what he can do, but it was too soon for him. Now he is trying to return to his normal performance, working hard.
“Angelo worked with Diop the complete pre-season and now they are the two centre-backs who must play.”
Balbuena’s involvement in the Copa America with Paraguay meant he arrived much later than other players for pre-season preparations.
He missed the first three pre-season friendlies, only appearing for the win against Fulham having missed out on the training camps in Switzerland and the Premier League Asia Trophy trip to China.
Throwing him right into action backfired, and it will be interesting to see if he will be able to snatch his starting berth from Ogbonna who has been perfect thus far.