Carlton Cole has told his West Ham United teammates to get over the disappointment of Saturday's defeat to Tottenham Hotspur and focus on coming back stronger.
Mark Noble missed a penalty as the Hammers failed to capitalise on a numerical advantage following Kyle Naughton's first-half red card on 29 minutes.
West Ham were then reduced to 10 men following James Collins's second booking after the hour mark, before debutant Eric Dier pounced with a stoppage-time "sucker punch".
"It was a sucker-punch. I don't think we deserved that. The boys are so disappointed," Cole told Sky Sports News.
"We've got to pick ourselves up, get ourselves out of the zone we're in – we don't want to be losing to Tottenham on the opening day.
"We should have made more of the one man advantage, and could have scored the penalty and set the tone for the rest of the game. We need to get this out of our system now."
Sam Allardyce's side travel to Crystal Palace next Saturday.
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