Danny Mills says Gareth Southgate has made "ruthless" decisions over his England World Cup team selection.
The England manager made 10 changes to the line-up that beat Nigeria in the first warm-up friendly, for England's 2-0 victory over Costa Rica on Thursday.
Marcus Rashford and Danny Welbeck scored in what was England's final match before heading to the World Cup.
Mills told Sky Sports News: "When Gareth came in people said he got the job because he was a yes man, that he wouldn't stand up and make ruthless decisions.
"I think we've seen that's not the case. He's left people out of his squad, that some people said should have been in it, Wilshere, Shelvey. He dropped Wayne Rooney very early on and has made big decisions."
"What he has done is creating an atmosphere, the players are relaxed. They're starting to enjoy playing for England again. Just look at the performance last night, it was energetic, they tried things.
"Rashford would get the ball and run at people, it wouldn't come off every time but he set the whole tone. I thought he was exceptional."
He added: "I think he would have known the team he wants to play before these two games, but there were probably two or three places up for grabs that he wasn't quite sure about.
"Perhaps a little bit of form or from injuries and where they're going to fit depending on who they play, I think he says himself it has gone according to plan, it couldn't have gone better. How they've dealt with the media, how performances have gone."
Southgate's World Cup squad currently has a total of 449 caps between them, which averages at fewer than 20 per person.
Gary Cahill is the most capped player with 60, while there are no other players with 50 caps.
In contrast, in Brazil in 2014 England had two players with 100 caps, Steven Gerrard and Frank Lampard. Wayne Rooney followed with 92.
"We don't have the choice to pick experienced players; we don't have that many players available that have in excess of 50 caps," Mills said.
"Gareth has decided from an early part of his tenure he wants to go for a younger generation, players he knows from U17s, U18s through to U21s.
"We've always said 'give youth a chance', let the youngsters express themselves and not be burdened with failures of the past. He's done that.
"But now people are moaning there's not enough experience, you can't win as England manager it's all about results."