Jamie Redknapp labelled West Ham's performance against Southampton as "shambolic" and said the new stadium is not an excuse for their early season struggles.
The Hammers, who left the Boleyn Ground to move to the London Stadium in the summer, have lost five of their six Premier League matches, including 4-2 defeats to Watford and West Brom.
They were again second best on Sunday as they were swept aside 3-0 at home by Southampton.
"It was shambolic from West Ham. I can't believe how poor they were," said Redknapp on Super Sunday. "There's a lack of confidence, but people aren't doing their jobs.
"The amount of chances Southampton had, it could have been 6-0."
Redknapp also said the change of stadium is "too easy an excuse", and added: "They weren't playing at the stadium when they conceded four goals to West Brom.
"You can blame the stadium but last year they had 13 points from these respective games and this year they have three. It's too easy an excuse, once you get out there you have to get on with it.
"It's been a really poor start and it's a real test for Slaven Bilic. They are missing a lot of spirit."
The Hammers' only league win this season came in their opening home game at the London Stadium against Bournemouth.
But they have a chance to improve their record in the coming weeks as they host both Middlesbrough and Sunderland.
Thierry Henry, who changed stadiums during his time at Arsenal, said: "We went to the Emirates and we struggled in the first year. It happens, regardless of who you are, it takes time to get used to it.
"But that doesn't mean you have to play like they did today. The attitude and commitment wasn't there, the way they were open was too easy, it didn't look like a West Ham team I know."
While Redknapp was critical of the display against Southampton, he does think the Hammers will turn their fortunes around.
"It will change, but they have to get players fit. They have too many good players for it not to change."