England captain Jos Buttler admitted the World Cup had been "incredibly disappointing" as the defending champions were pushed to the brink of elimination on Thursday.
England suffered an eight-wicket trouncing at the hands of Sri Lanka who chased down a 157-run target with almost 25 overs to spare.
It was a fourth defeat in five games for England, who slipped to ninth in the 10-team table and need to win their four remaining games to have any hope of even squeezing into the semi-finals.
Three of those games are against India, Australia and Pakistan.
"It's incredibly tough, an incredibly disappointing tournament. As captain, you feel that a lot," said Buttler.
"We've been short of our best by a very long way. I'm disappointed for myself and the boys that we've not shown a good account of ourselves.
"There's no clear answer. If there was one golden nugget that we're not doing then we'd pick that up."
Buttler's own form at the World Cup has mirrored England's misery.
He made 43 in the opening loss to New Zealand and managed just 52 runs in the four subsequent matches.
"I can't fault the guys' efforts, we're just a long way short of our best," he added.
"As captain, you want to lead from the front and play well. I've been a long way short of my best and that's filtered through to the rest of the team."
England coach Matthew Mott admitted that the team will face serious criticism for their limp efforts.
Their only win has come against Bangladesh while a stunning defeat to Afghanistan also dented their hopes.
"We've got some serious soul searching to do, we're going to cop it, we know that and quite rightly, we didn't perform anywhere near our level," Mott told the BBC.
"I still think we have a team good enough to win this tournament, but clearly we haven't put it together when it matters. Unfortunately we're out of form at a very bad time for us."
'I'm still man to lead England', says Buttler despite World Cup misery
A defiant Jos Buttler insists he is still the man to captain England despite presiding over a doomed World Cup campaign.
England suffered an eight-wicket trouncing on Thursday at the hands of Sri Lanka who chased down a meagre 157-run target with almost 25 overs to spare.
It was a fourth defeat in five games for England, who slipped to ninth in the 10-team table and need to win their four remaining games to have any hope of even squeezing into the semi-finals.
Three of those games are against undefeated two-time champions India, five-time winners Australia and 1992 champions Pakistan.
When asked if he is still the man to lead his country the 33-year-old simply replied: "Yeah".
"I think you're always questioning as captain how you can get the best out of players, how you can get the team moving in the right direction.
"I certainly have a lot of confidence and belief in myself as a leader and captain and first and foremost as a player, but if you're asking if I should still be captaining the team that's a question for the guys above me."
Asked if England's World Cup is over, Buttler admitted: "It certainly looks that way."
Buttler has been in charge since June last year when he succeeded Eoin Morgan who led England to victory at the 2019 World Cup.
Buttler has enjoyed success, leading the team to the World Twenty20 title in Australia last year.
In India, however, England have looked predictable and tired -- on Thursday, all of their starting eleven were over the age of 30.
In five games at the World Cup, England have lost to Afghanistan and suffered a 229-run mauling by a rampant South Africa.
"It's incredibly tough, an incredibly disappointing tournament. As captain, you feel that a lot," added Buttler.
"We've been short of our best by a very long way. I'm disappointed for myself and the boys that we've not shown a good account of ourselves.
"There's no clear answer. If there was one golden nugget that we're not doing then we'd pick that up."
- 'Long way short' -
Buttler's own form at the World Cup has mirrored England's misery.
He made 43 in the opening loss to New Zealand and managed just 52 runs in the four subsequent matches.
"I can't fault the guys' efforts, we're just a long way short of our best," he added.
"As captain, you want to lead from the front and play well. I've been a long way short of my best and that's filtered through to the rest of the team."
England coach Matthew Mott admitted that the team will face serious criticism for their limp efforts.
Their only win has come against Bangladesh while a stunning defeat to Afghanistan also dented their hopes.
"We've got some serious soul-searching to do. We're going to cop it, we know that, and quite rightly. We didn't perform anywhere near our level," Mott told the BBC.
"I still think we have a team good enough to win this tournament but clearly we haven't put it together when it matters. Unfortunately we're out of form at a very bad time for us."