Kevin Wimmer admits Tottenham did not play well.
Speaking to SpursTV he did not try and spin the facts, insisting the team were not up to their usual standard.
He said: "It was very disappointing. We were a bit better in the second than the first but we didn't play well.
"It was a very unnecessary result tonight but we will turn it around on Saturday. We will give it our all to do that."
Ryan Mason was more animated, insisting the manner of the goal, coming from a set piece left the team angry.
He said: "We were very angry to concede from a set piece and from there we were always chasing the game.
"We need to recover well and put in a good performance on Saturday so we can forget this."
Michail Antonio put West Ham 1-0 up within the opening 10 minutes and Spurs could not break a resolute Hammers defence which has stood firm to record clean sheets in wins over Arsenal, Liverpool and Manchester City this season.
Tottenham dominated possession with 65 per cent but could only manage two shots on target from nine attempts.
Spurs remain in second place in the table while West Ham stay in sixth, but Manchester City's loss means they are just one point off the Champions League places.
Tottenham face Arsenal at the weekend, who lost to Swansea City at The Emirates.