England manager Gareth Southgate said he was "immensely proud" of his young side after they went out of the World Cup in the semifinals to Croatia.
Kieran Trippier scored inside five minutes but Croatia hit back in the second half through Ivan Perisic to force extra time and Mario Mandzukic netted the winner to send England home.
"We played extremely well in the first half, given the size of the game," Southgate told a news conference. "I was really pleased with the way we controlled possession. Our decision making was good. When you're in charge of the game and have the chances we had, you have to take a second goal at that point.
"We had a little less composure with the ball in the second half. Maybe that was a consequence of being ahead with the least experienced team in the finals, with an opportunity to get to a World Cup final... whether that had an effect, subconsciously, I don't know. We then had to weather sustained pressure as Croatia came really strong. They have some outstanding players and some huge experience."
He added on the BBC: "I am immensely proud by the way the players have played and we can see by the reaction of the supporters, they felt the same. It was difficult to say anything that will make them feel better at his moment. They have not experienced that before playing with England and it also shows that it can be a memorable experience playing for their country."
Mandzukic pounced on a defensive lapse from John Stones to fire past Jordan Pickford in the 109th minute at the Luzhniki Stadium after Perisic's volley had cancelled out Trippier's spectacular early free kick.
England faded badly after Perisic's equaliser as Croatia seized control of the midfield battle, and Southgate admitted he did not feel he had the options on his bench to put his team back on the front foot.
"I think throughout the game we were looking at how we might stem the tide, but there weren't clear changes that we thought we could change the situation," he added. "There were times when we just had to regain some composure in our defending and start to play with the ball again.
"There was a period of about 20 minutes in the second half where we stopped playing and lost that bit of composure.
"The biggest thing is you see the supporters at the end and their reaction. That tells you what the players have given, not just tonight but over the period. I can't ask any more than what the players and staff have given."
The defeat brought an agonising end to England's best run at a World Cup since 1990, and after the match Southgate insisted his team had done their country proud despite being undone by fine margins.
"Knockout football is fine margins and when you have spells in a game against a side with real quality you have to make them count," he told ITV Sport. "We probably needed that second goal early in the game.
"I think we are where we are as a team. We've come an incredibly long way in a short space of time. The experiences of the matches with Colombia, Sweden... the whole thing is probably beyond where we thought we might be able to go. Tonight we weren't quite there, but the team will be stronger for that.
"It's very difficult. As we reflect over the next few days there will be a lot more positives, but tonight it's so difficult for everyone to take. We were so close to something that was almost unimaginable at the start.
"But the players have to look at the reaction of the supporters and you don't get that if you haven't given everything. We left everything out there. We'll look at the goals and the chances, but for sure over the six or seven weeks we've been together I don't think we could have given more than we did."
Asked whether this World Cup had been some of the best few weeks of his life at his new conference, Southgate said: "Yes, no question. I'm just conscious we've just lost a massive, massive game and I don't want to be seen to be moving on too quickly.
"The opportunity we had we shouldn't overlook. But no question, for everybody in our party, I wanted them to create memories that are with them forever, for them and for others. I think we've all had an incredible experience. For me, that's what sport should be about. You give everything you have, build friendships with your team, give everything for your country and play in a way that you hope connects with the fans.
"The players have played and conducted themselves in a manner that has absolutely done that. IF we've brought joy back home, which I know we have, then that's been worthwhile. We should be proud of that. We're hugely disappointed not to take the country one step further and give them everything they hoped for. But, in time, I'm sure we'll reflect upon the progress we've made."
Information from Liam Twomey was used in this report.