Watford - Manchester United starlet Marcus Rashford will only deliver for England if left to his own devices on the pitch, his club and international captain Wayne Rooney warned on Wednesday.
Rashford, 18, was the headline inclusion in the 23-man squad for Euro 2016 announced by manager Roy Hodgson on Tuesday.
Rooney was only 18 when he exploded onto the international scene with England at Euro 2004, but he said that he would not be muddling Rashford's mind with unnecessary advice.
"Personally it was a good tournament for myself, but with Marcus in this tournament, for me he doesn't need much advice," Rooney told a press conference at the England team hotel in Watford, north of London.
"Let him play. As a young lad, that's how you see the best of him. Sure, in the future you can work on more advice, more instructions, but with some players you just let them play and he fits that category."
Rashford was named in England's Euro squad just 96 days after his United debut in February, having scored eight goals in his first 18 appearances for the club.
He took less than three minutes to find the net on his England debut in last Friday's 2-1 win over Australia and Rooney branded his emergence "incredible".
"He's certainly showed what he can do in his first game for England, getting his first goal in the first couple of minutes," said the England skipper.
"I think what's pleasing about him is his attitude. It's first-class and that's shown around the hotel and on the training pitch and he deserves it. He could be a real positive for us."
Rooney's words were echoed by Hodgson, who jettisoned midfielder Danny Drinkwater and winger Andros Townsend from his provisional squad in order to make room for Rashford.
"Rashford's had that fantastic end to the season and he's a very, very interesting player," said Hodgson, whose side face Portugal at Wembley on Thursday in their final warm-up game ahead of the Euro.
"He has special qualities and I think that's been recognised by everybody. It will be very interesting to see in a squad of 23 whether or not he can bring those qualities to bear at an even higher level."
Hodgson's squad features five out-and-out strikers and a host of attack-minded midfielders, and he said it was a considered decision to arm himself with creative players.
"If anything, the balance does tilt towards attackers and offensive midfielders," said Hodgson, whose side beat Turkey 2-1 in their first pre-tournament friendly.
"That was a conscious decision. That's where we think our strength lies. We have a lot of players in that position who are good enough to represent England both now and in the future."
Hodgson confirmed that Rooney would start against Portugal and hinted that he will play something approaching his strongest team.
Portugal, who have also qualified for the Euro, will be without talismanic captain Cristiano Ronaldo, who is sunning himself in Ibiza after winning the Champions League with Real Madrid.
Hodgson revealed that the Football Association had selected Portugal as opponents partly due to the similarities between Ronaldo and his club-mate Gareth Bale, the chief threat posed by England's Group B rivals Wales.
"One of the things we thought about with Portugal is Ronaldo is a very special player and special talent," said Hodgson. "We were thinking Bale is in a similar position.
"We were thinking about them having a special individual. We're happy with the two opponents we've had so far and expect another tough test tomorrow night."