Roy Hodgson admits England's World Cup woes have them in a 'realm of despair' and says it could take six years to rebuild.
England head into Tuesday’s meeting with Costa Rica in Belo Horizonte already out of the tournament following back-to-back 2-1 defeats by Italy and Uruguay - and in danger of becoming the first England side to leave a World Cup finals with no points.
Hodgson concedes that England have been dealt a few ‘painful’ lessons in Brazil this summer, and is aware there will be no quick fix to the issues which have been highlighted.
He has made it clear he will not be walking away from his post, and has the backing of the Football Association to continue until Euro 2016, but the former Fulham and Liverpool boss has warned it may not be until the next World Cup, or even the 2020 European Championships that the next crop of English talent is ready to challenge.
Hodgson, who has made nine changes to his starting XI for the clash with Costa Rica, said: “I’ve realised that, at this top level in a World Cup, it is unbelievably unforgiving.
"A moment of misfortune can throw everyone into a realm of despair that you didn’t know was possible.
"I've learned how painful it is to build up your hopes and to see a lot of good preparations be of no avail because it didn’t get us to where we wanted.
"This game (against Costa Rica) will tell me a lot about the players. It's been a very tough few days and it’s hard to pick yourselves up for a game that, even if you do well in, serves no purpose.
"The 100-cap players will find that hard. We’ll learn a lot about the others.
"I've liked what I've seen around the hotel and in training. I'm now giving them the opportunity, not because I can, but because this is a good team and they can go and win the game. I hope they prove me right.
"We just hope the next two, four to six years will bring some dividends.
"We are no longer capable of going through, but we're trying to build the confidence and use the potential of some quite talented players who have emerged on the scene.
"All we can do is hope that, when these players are reaching their best years at the age of 28 or 29, the work shows some dividends."
Hodgson added on the decision to freshen up his side: "We have a different team and I want everyone to go home having taken part and played in this game.
"We want to take some encouragement from that and recognise that this is a top-class international on the biggest stage.
"Costa Rica have taken the football world by surprise and this is a chance to show that we can compete, a chance to show we have a lot of pride in our performance.
"This is a great opportunity for the team to go out there on this fantastic stage and show that they have a lot of potential and are already good enough to wear the England shirt. And I believe they will not let us down."