Neil Dewsnip wants his side to "show their character" on Wednesday, when they face their second game with Croatia at St. George’s Park.
The Young Lions lost 2-1 against the Croatians on Monday afternoon, seeing a half-time lead cancelled out by two quickfire goals after the break.
And boss Dewsnip admits he was at something of a loss as to why his team couldn’t replicate their first-half performance when Chelsea striker Alex Kiwomya put England ahead.
England U18s 1-2 Croatia U18s
International Match
2pm, Monday 3 March
St. George's Park
"I thought we started slowly, when they did quite well, but we weathered the storm and probably stole a goal and then we played quite well up to half time," Dewsnip told TheFA.com.
"I thought we were quite comfortable and could only get stronger.
"Unfortunately, in the second half we just didn’t get going at all for whatever reason and the players are really disappointed.
"I guess it’s one which they can’t explain, and I can’t either really – it just didn’t happen for us in the second half."
With another day of training with his squad before their second game against their Croatian guests on Wednesday, Dewsnip has now challenged his players to come back strongly.
Highlights of the game at SGP
"These are still young players, and if nothing else from today, they will have learnt the importance of defending," he added.
"In the context of the overall season, when we’ve played really well in all the games, the law of averages with young players is that they don’t play that well all of the time.
"So we’re disappointed to lose the game today and disappointed with the second half, but I’m really looking forward to Wednesday to see if they’ve got any character."
Watch the full interview with Dewsnip in the video player above.