Rio Ferdinand has urged England boss Roy Hodgson to start defender John Stones at Euro 2016.
Stones will battle with Gary Cahill and Chris Smalling for a place in the England back four for Saturday's opening group game against Russia in Marseille.
The 22-year-old Everton centre-back has had a testing season domestically and did not start the final warm-up fixture against Portugal on Thursday.
But former England defender Ferdinand believes it is essential Stones is given the necessary experience in France this summer.
Ferdinand wrote in the Sunday Times: " I mean no disrespect to Gary Cahill but Cahill is not going to play at the World Cup (in two years' time). You could not say Cahill and Smalling are a cast-iron partnership. So play Stones.
"It is about developing players with talent. There is no doubting that, this season, Stones has made mistakes and he has been hammered for them. But does that mean he does not have the potential to be a world class centre-half? No. It just meant he has to learn.
"Someone with promise, who could go on and be a world beater - let him go on and develop the experience he needs.
"I found it took me 10 or 15 games to really feel comfortable in an England shirt and England dressing room."
Ferdinand, capped 81 times by England, also urged Manchester United striker Marcus Rashford to soak up as much of the experience in France as possible.
As a teenager, Ferdinand was a member of England's 1998 World Cup squad in the same country and felt it was a key learning process for him despite not seeing a minute of action.
He added: "I know, first hand, the benefit Rashford will get from France. I was very fortunate to go to the World Cup in 1998 and be a sponge, be a student and enjoy the tournament because I did not have any expectations of playing.
"He will get more minutes than I got in 1998 but he will not be an integral member of the team and he can say to himself, 'In two years' time I want to be the first name on the sheet at the World Cup, so what do I need to learn to make that happen?'."