"Humiliated" West Ham manager Slaven Bilic says Saturday's 5-1 Premier League home defeat by Arsenal leaves him "under pressure".
Alexis Sanchez's hat-trick helped the Gunners go second in the table with victory at London Stadium.
Andy Carroll, returning from injury for his first game since 18 August, scored West Ham's consolation with a header.
"I don't want to feel like this. I apologise to the fans and anyone to do with West Ham," Bilic told BBC Sport.
"It was bad. I feel disappointed. I feel humiliated and it's my responsibility.
"I feel under pressure. I put the pressure on myself. But the pressure is not a problem. Things have to change."
Arsenal profited from an error by Angelo Ogbonna for their opening goal, scored by Mesut Ozil after Hammers centre-back James Collins came off injured.
Alex Oxlade-Chamberlain also netted for the Gunners - between Sanchez's second and third goals.
West Ham, beaten 4-1 by Manchester United in the EFL Cup on Wednesday, have not won in the league since a home victory over Sunderland on 22 October.
They are one point above the relegation zone, and will drop into the bottom three if Hull win at Middlesbrough on Monday.
"I am not looking for excuses. Yes we had injuries and mistakes, but we were not good enough," Bilic said on BT Sport.
"I have to be honest and say we don't have the intensity. We don't have it the same as last season, even in training.
"We were in a serious situation before this game, which we don't like. The players know that, but it's not only about knowing. It's about sacrificing and dedication for the game."
Match of the Day pundit Chris Sutton said Bilic's criticism of his players is a concern.
"When your manager is questioning your commitment and intensity there should be alarm bells ringing," said the former Blackburn striker. "I can't see them getting anything out of Liverpool in their next game and then they have Burnley, Hull, Swansea and Leicester. They are huge games for West Ham."
The Hammers finished seventh in the league last season but have won only three games since leaving Upton Park for London Stadium.
"Of course we are in a relegation fight and of course the players know that. It's not that they don't care," Bilic added.
"Am I positive I can turn this around? Yes I am. Did I do enough last season to get some credit? I think I did.
"We can do it because these players have done it, but the dedication to the cause is missing."
Ex-QPR striker Bradley Allen at London Stadium for BBC Radio London
Arsenal were at their brilliant best and, once they got themselves in front, it was just a matter of time before they built on their lead.
West Ham have to thank their keeper for keeping the scoreline down.
It was a thumping victory for the Gunners and they are genuine challengers for the league title.