It was a frustrating defeat as England made numerous defensive errors, with Ronald Koeman's men eventually taking advantage when Stones' inexplicable dallying led to Kyle Walker's own goal.

Quincy Promes wrapped up the win after Ross Barkley overplayed at the back, but Southgate vowed to encourage his players to keep playing with courage and confidence in the defensive third.

"It's difficult to know why individual errors like that could happen and can spread, not just from one or two players," the England boss said.

"I can only say that to play the way we want to play takes courage and when it doesn't work out then it's very difficult for the players.

"It's easy to turn around and kill them but we have some defenders who are prepared to take the ball in areas where many defenders in the world aren't.

"It's been the bedrock of how we've progressed, and we have to continue it but of course, we can't make the mistakes we did."

Former defender Southgate was particularly protective of Stones after his glaring error in Guimaraes, a mistake potentially born from the Manchester
City centre-back's lack of game time towards the end of the campaign.

"He knows that I am here to support him," the Three Lions boss said.

"I know he is going to get criticism, and he's had a difficult end to the season in that he was not playing regularly at his club.

"We still think he has been our best centre back, has huge qualities and huge potential to be a top player.

"But he has had so little football at the end of the season that the sharpness and fatigue as the game wore on were definitely factors in what has happened tonight.

"Joe (Gomez), who was with us (only from) two days ago, hasn't played either, and Michael Keane hasn't played in this sort of a game.

"So I think Stones and (Harry) Maguire are our best two, and I have to be there to support in their difficult moments."

The defeat was made all the more crushing by Jesse Lingard's potential winner being ruled out by the video assistant referee, and the fact England now have to line up in a third-place play-off against Switzerland on Sunday.

"We have to (give everything)," said Southgate, who confirmed goalscorer Marcus Rashford was taken off with a bruised foot.

"We have thousands of fans here, and we owe them that we give absolutely everything.

"The mentality of the group is that we do that right the way through, and we have to do that for Sunday. It is no use complaining about it.

"We have to see who can go, and there are a couple of injuries, certainly a few with cramp, and we have to try to freshen it. That's our best chance of getting a result, to freshen it as much as possible."

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