The Hammers took the lead through Said Benrahma, who found the back of the net with a powerful strike from outside the box.
However, a defensive mistake allowed Wilfried Zaha to level the scores four minutes before half-time.
The hosts were awarded a penalty in the 80th minute of the game, only for VAR to overturn the decision.
In the fifth minute of added time, Michail Antonio wasted a brilliant opportunity to grab the winner with a poor cross.
Seconds later, Michael Olise popped up with the decisive goal by curling a deflected effort over the goalkeeper to seal three points for the away side. Moyes was unhappy with his team’s performance.
In his post-match press conference, the Scottish boss said (as per football.london): “It’s gutting, but we didn’t deserve to win. We got a goal ahead probably against the run of play. We gave away a terrible goal.”
West Ham made some heavy investments on several new recruits in the summer transfer window, including Gianluca Scamacca, Emerson Palmieri and Lucas Paqueta.
However, their performances have been hugely disappointing this season. Following eight losses from 14 matches, the Hammers are currently 15th in the league standings.
They provided a tough contest in their 1-0 defeat at Manchester United last week but were second-best throughout the game on Sunday.
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