A Ward-Prowse goal in the 36th minute meant West Ham went into the break leading the game against the reigning champions at home.
But second half goals from Jeremy Doku, Bernardo Silva and Erling Haaland saw Manchester City winning the game 3-1 and leaving the London Stadium with all three points.
The West Ham goalscorer conceded that the result was disappointing and feels it is disheartening that the Hammers could not respond once Manchester City came back into the game.
However, he did admit that Manchester City were far too good and thinks they could have done little to stop those goals from the away side.
The Hammers star told the BBC: “Disappointing.
“When you come against a Man City team you’ll be up against it and sometimes you have to hold your hands up and say fair play.
“All of their goals were of real quality, just a shame we couldn’t respond.”
West Ham will be in Europa League action on Thursday night when they will take on Backa Topola.