West Ham United were beaten 4-0 by Manchester City at the London Stadium in their last outing.
West Ham were beaten 4-0 by City, but the scoreline did not give an entirely fair reflection on the game.
The Hammers had actually threatened on occasions, but they were undone by their defensive work.
City scored a number of tap-ins from close range during the contest, and Pellegrini was frustrated with the ease with which Pep Guardiola’s men were allowed to score.
He said: “I am not happy about the goals we conceded – it is difficult to understand how we conceded such easy goals – but I am happy about our spirit and the way we played from the first minute to the last, and the fact the players always believed they could win.”
West Ham have shown a vulnerability at the back this term, even though both their centre-backs have earned praise.
Fabian Balbuena and Issa Diop have both impressed since arriving at the London Stadium this summer, but they were powerless to resist on Saturday.
West Ham have taken just 12 points from their opening 13 Premier League matches, after a disappointing start to the campaign.
Pellegrini’s side are next in action when they take on Newcastle United, when they will be under pressure to get points on board.
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