Roy Hodgson admitted he was left bitterly disappointed by Liverpool's Carling Cup exit at the hands of Northampton Town on Wednesday night.
Milan Jovanovic appeared to have set the Reds on their way to victory with a clinical ninth-minute strike, but Billy McKay drew Northampton level early in the second half.
Kevin Thornton then put the Cobblers ahead in extra-time and though David Ngog levelled, Liverpool were left stunned after the League Two side claimed a 4-2 penalty shootout victory.
Afterwards, Hodgson confirmed he shared the fans' frustration at the defeat.
"I didn't think we came anywhere near to what I'd hoped to see from the team except perhaps in the last 15 minutes of extra-time when we really made a superb effort after going 2-1 down," the boss told a post-match press conference.
"It didn't look good (after going behind), but we certainly did everything we could to take the game to them and maybe we were a little bit unlucky not to get a third goal in that period because we had a good grip on the game and both teams were tiring.
"But when it goes to penalties and you're at home in front of the Kop, your hope is that the players will have the composure and confidence to win the shootout. But we didn't and all I can do is congratulate Northampton and apologise to everyone. The fans who came tonight obviously expected to see us win, I expected to see us win but it wasn't to be."
Liverpool made wholesale changes for the cup tie to the team that had taken to the field for Sunday's clash with Manchester United at Old Trafford.
Hodgson added: "The fans know we took a risk by playing a totally different team. I thought the fans were very good as usual and the support for the team was excellent.
"I don't think fans will see it any differently to the way I saw it, they won't be any more disappointed than I am.
"There is nothing I can say that will make them feel any better because they're going home bitterly disappointed that we're out of the Carling Cup and what's more, we've been knocked out by a team several leagues lower than us.
"There is nothing to say except I thought the effort was there, we didn't lose because we were casual in our approach or lethargic in our play, we lost unfortunately because we defended poorly on a couple of occasions and didn't use the ball well enough with the possession we had.
"Basically, there are 12 or 13 players if you take Fabio Aurelio, who didn't play tonight and are the more famous names. But outside of them, the players we had out tonight are the ones we have and I thought it was a good opportunity for them to show what they can do at Anfield.
"I have to say, Northampton were clearly better than one would have expected from a team playing where they play. We must give them credit. We knew they were quite a good team from watching them, but I honestly believed with the quality of players we had on the field, with both international and Barclays Premier League experience, we would be good enough to win the game - but we weren't."
Hodgson acknowledged he was disappointed by the manner of his side's performance and insisted that the defeat was the responsibility of both players and manager.
He said: "The fact is these players have to accept responsibility. I have to accept responsibility for changing a lot of players in the team, but I did it because I thought the players I put on the field would be good enough to go out and win the game.
"They weren't, so the obvious conclusion to that is that I shouldn't have changed so many players and should have let some of those players who played against Manchester United play tonight, but I honestly believed the team we put out on the field would have been strong enough to get a result.
"But we weren't and that's because we didn't play well enough, didn't pass the ball well enough throughout the game and you must give some credit to Northampton who worked extremely hard and I'm sure they'll go away feeling they have stolen nothing here tonight and were worth their victory."
He continued: "They (the players) will have to do a lot of work to get themselves back into favour, but it's early doors for some of them. Some of the players who played tonight are still quite young.
"But it's enough for me to say I am very disappointed and you can see that on my face. I did not expect to be sitting here having lost a penalty shootout, which is the worst possible way of losing matches I can assure you. I have lost a UEFA Cup final on penalties, so I know how bitter they are, what a lottery they are and what damage they can do to the players who miss them.
"It's one game. It's a very disappointing game but there are lots more games to play and I would expect these players to be very, very disappointed about their performance tonight, to learn from it, to bounce back and if they're going to be Liverpool players, to kick on from this very low point in everyone's career."
Reporters quizzed Hodgson on how big of a setback he felt the defeat was to the club.
He responded: "The fact is the Carling Cup is a competition which we are capable of doing well in and this is the third round, playing against a lower league club, so if it doesn't result in a victory it is a very negative thing.
"It's one of many setbacks we're facing at the moment and it's a tough period to work and live through, but we will work and live through it. We will survive it and get better. I will learn an awful lot from this defeat tonight about an awful lot of people.
"It's not just myself who will be disappointed and upset that things didn't go our way - there are lots of players who played tonight who will be disappointed as well."
Jonjo Shelvey's appearances as a substitute in extra-time helped lift Liverpool, with the midfielder playing a part in Ngog's equaliser.
Hodgson said: "He did well but the fact is he came on in extra-time and people were tiring. We think Jonjo Shelvey is a player with a bright future, but I have to say I am not in the mood for talking about positives.
"We wanted to do well in the Carling Cup and we haven't. We were given a fairly kind draw if you look at the other teams we could have drawn. If you get a team from three leagues below you, you're expect to win and when you don't win, then you can expect to be criticsed from the top downwards.
"We must all take responsibility and I am bitterly disappointed that the team I had so much faith in did not repay that faith this evening, with the exception of one or two."