Thomas Tuchel says he learned a lot about his players' quality and character as experimental England lumbered to a draw in Friday's World Cup audition against Uruguay.
It is just eight weeks until the manager selects the group he believes have the traits and talent to replicate Sir Alf Ramsey's 1966 heroes by triumphing on the world stage.
Tuchel chose an expanded 35-man squad for the final camp before taking that decision, with 19 players spending some time on the field in England's penultimate friendly.
It was a stop-start performance against physical Uruguay, featuring divisive defender Ben White's first international goal and some poor officiating, but the 1-1 draw was beneficial overall for the national team boss.
"I learned a lot because it was a tough opponent," Tuchel said after the 1-1 Wembley draw.
"You just see it in the details. You learn a lot in the details, how is the behaviour and you see the level.
"If you play against (Manuel) Ugarte, if you play against (Federico) Valverde in midfield, you see the level.
"You play against the wingers and these defensive players, it's a high level and then you instantly see so we needed this kind of test. I'm happy that we did it the way we did it and we learned a lot."
Tuchel always knew Marcelo Bielsa's Uruguay would be a "feisty and tough" opponent for England, who go from hosting the side 17th in the FIFA world rankings to welcoming 19th-placed Japan on Tuesday.
Harry Kane, Declan Rice and Bukayo Saka are among 11 established players returning to the camp for that friendly, changing the dynamics of the group.
"The guys who came, they need to relearn our principles," Tuchel said. "They haven't been in camp for three months, so they also need to relearn it. We have three days of training.
"Japan plays a very unique style with normally a back five, so wing-backs and then two 10s and then switching sides, so we need to be on point tactically to have solutions.
"But this is what we expect from the guys who got a break and we will deliver some solutions, and they need to put it into life. But this is our work from (Saturday)."
Among the main positives on Friday was the performance of debutant James Garner.
The Everton midfielder earned the player of the match award and praise from his manager, who had said moments before that he would pick Real Madrid star Valverde if he could have any player from the Uruguay set-up.
"I'm very happy (with Garner) - he's our mini Valverde," Tuchel said.
"He's getting there, and he played very, very good. I was quite sure that he will play good because he has this natural confidence and he's just very physical. He won a lot of balls.
"I think there are some situations where he can be a little bit more open in the body position and drive maybe a little bit more through midfield with a little bit more confidence.
"I think in the last 10 minutes of the first half, he was involved in some ball losses that cost us a bit of confidence.
"But overall I was very impressed with the way he trained and the way he behaved. The way he played was good."