Phil Neville gave Beth Mead a "rocket" earlier this year and feels she is now a player looking to "go to the moon".
The Arsenal forward was named player of the match on Saturday as Neville's England beat Denmark 2-0 in their penultimate warm-up game ahead of the Women's World Cup.
Mead produced the cross headed in by Jill Scott for the second goal at Walsall's Banks's Stadium, having earlier delivered a free-kick in the build-up to the first, netted by Nikita Parris.
The 24-year-old, who made her senior international debut just over a year ago, went into the Denmark friendly having scored three goals in her previous five England appearances in 2019.
Mead scored two goals in the triumphant SheBelieves Cup campaign in the United States, including a memorable strike in the opener against Brazil.
Following Saturday's match, it was put to Neville that Mead must be knocking on the door of his starting XI.
And the Lionesses boss said: "She's inside the door, to be honest. She's ready to play.
"She wasn't six months ago. We had very harsh words with her. We had to really tell her a few home truths about somebody that was just probably at the level she was happy with, but we knew she could go to a different level. Working with Joe (Montemurro, Arsenal's manager), we both had massive belief in her.
"Now we're seeing someone that's beginning to think like she could be a real threat for us in the World Cup.
"She's tougher mentally. She has aggression, doesn't give up. We've set her a challenge. Her delivery is as good as any in the women's game, and we have her hitting 20, 30, 40 balls every day into areas. It's working. But we've given her some real tough love.
"If there's one player I've given the biggest rocket to, it's her. It was in January, over the phone. We laugh about it now. She knew at the time. She didn't argue back and made a promise to me she would make the improvements."
He added: "She's the nicest girl in the world – and that's what I said, 'stop being too nice'.
"I left her out (of the starting XI) for the USA game at SheBelieves and that was the first time she got angry with me. When she walked out of the room, I actually thought, 'she's now beginning to be a player'.
"She'd scored this unbelievable goal and expected to play against the USA. I said, 'you're not playing, be ready to come in' and she literally stormed out of the room, angry. And I thought, 'job done, she's ready now'.
"The anger I see in her now, the aggression and determination, and the practice... The penny has dropped.
"It's like, 'do you want to go to Blackpool on your holidays, or do you want to go to the moon?' She now wants to go to the moon. Before she was happy just to go to Whitley Bay and have fish and chips."
When asked about the phone conversation, Mead said: "He probably didn't tell you everything he said to me! Sometimes as a player you need that, you get a bit complacent."
Mead said what she heard from Neville prior to the SheBelieves Cup "made me kick into another level" and added: "I definitely believe it was the best thing for me and I think me and Phil are on a very good level right now.
"He got the best out of me and now I'm pushing to be better every day. I've always been a nice girl, but I've had to get a little bit tougher."
Mead, who has started each of the last two friendlies, has her sights firmly fixed on being in the XI when England open their World Cup campaign against Scotland in Nice on June 9.
"Now I'm pushing to be more than just in the squad," said Mead, who helped Arsenal win the Women's Super League title in 2018-19.
"I want to be in that starting XI now. I want to give Phil the biggest headache on June 9, to be like, 'I can't not put Beth in this team'."
England's final warm-up game is against New Zealand in Brighton next Saturday.
