West Ham manager Slaven Bilic blamed a lacklustre first-half performance for Saturday's 2-1 defeat at home to Leicester City.
Bilic's men were unable to repeat the form that secured a surprise 2-0 opening-day win at Arsenal, as Shinji Okazaki and Riyad Mahrez were on target to give Leicester the advantage before the break.
Dimitri Payet finished emphatically to halve the deficit after 55 minutes, but Bilic felt his players left themselves with too much to do.
"It is a bad result of course after a good start," he told BBC Sport. "We didn't play good enough in the first half. We started well, but after that we were second best.
"We lost the game in the first half. Two-nil down is very difficult to come back from. We are very disappointed."
To compound West Ham's woes, goalkeeper Adrian was sent off in stoppage time after coming for a corner and catching Jamie Vardy with a dangerous, studs-up challenge.
Bilic accepted that referee Anthony Taylor made the right call, but insisted there was no malice on Adrian's part – the two players having clashed early on in the match, when Vardy was booked after 11 minutes.
"Initially I thought it was not a red card, but then I saw the replay and it is dangerous play," Bilic added.
"It was obvious Adrian didn't mean to cause harm. I am more than sure it was not deliberate. He was just following the ball and was unlucky."
