But the Celtic starlet has already come of age in a Hoops and Scotland shirt.

What's more, the player who returns to pre-season training in three weeks is anticipated to be even stronger, fitter – and better.

That confident prediction comes from Bobby Petta, who is perfectly placed to judge as a former winger with Celtic, with the ex-Parkhead favourite now carving out a career as a personal trainer and fitness coach.

The flying Dutchman knows exactly what demands are placed on a player like Forrest, and what is required to ensure you are in the best physical condition to deliver the best return from your talents.

After being carefully nursed through his first full season as a Celtic first-team player by Neil Lennon, who was very mindful of Forrest's hamstring and pelvic issues, the Ayrshire kid was allowed to go full tilt in the campaign just ended.

His 46-game master-class was only brought to an end abruptly when Forrest was cynically fouled in the Scottish Comminutes League Cup Final against Kilmarnock in March.

The bruising around his right ankle ruled him out for the remainder of the season, both for Celtic and Scotland, and ensured he would not have a difficult decision to make in terms of participating in next month's Olympics.

But, before he fell foul of that foul, Forrest had done enough to convince everyone he was the real deal, and Petta is a fully-paid-up member of his fan club.

The ex-Celt said: "James is still only 20, and has deservedly won all these Young Player of the Year awards.

"It was a pity his season ended early when he got a kick on his ankle. But, of course, such trauma injuries are something you can't do anything about."

Petta has been impressed with the way Forrest and Celtic have managed his problems, which even saw him consult a London specialist who prescribed specially-designed footwear to help prevent further groin and hamstring injuries.

The Dutchman recognises that explosive players such as Forrest can be a martyr to this type of problem and said: "When Ryan Giggs started out in the Manchester United team, he also suffered a lot of hamstring problems.

"But, through a combination of flexibility exercises and strengthening, he overcame this to go on and have a very long and successful career.

"There is no set answer. It's about finding whatever suits the individual and their needs.

"Hopefully, they have now done this with James. From what I have seen, I'm sure they have, and now he will be able to play more and more games.

"He managed 46 last season before he got that ankle injury, and that is a big increase on the previous season.

"Playing week, in week out in the SPL is a very big step up for someone so young.

"There are high demands on you physically, especially playing in his position. But, if you train properly and are sensible with diet and rest time, it shouldn't be a problem.

"What you have to accept is that football has changed and is no longer the game it was even a few years ago.

"There is now a lot of science involved in it. The old school approach just doesn't do it any more. Playing over 40 or 50 games a season is a lot because of the intensity."

Petta – who is taking his football A-licence and is focusing more and more on one-to-one coaching while also expanding his fitness business in Glasgow – reckons there is much more to come from Forrest.

The Dutchman added: "I'm sure James will be stronger for the experience of playing so much last season, and at a very high level, including in Europe and with Scotland.

"If he can continue to limit the number of injuries, he can get better and better.

"As a coach, you have to be careful with young players, and Neil has been with James.

"It's also important any youngster coming through has a good relationship with the training and medical staff, and James has that.

"That's got a lot to do with the fact he is keen to learn and to improve, so will listen to what he is told."

Petta thinks this will provide Forrest with the prefect platform to reach the very top of the game.

He said: "I believe James can go all the way because he has all the attributes to achieve whatever he wants in the game.

"He can play either side, is fast, and has now added more goals to his game.

"A lot of clubs have been watching him already, and he has been praised by managers and coaches of teams he has played against in Europe.

"But this is not affecting him because he is a down-to-earth lad and a nice person.

"James' attitude is fantastic and he has a strong desire to succeed. You can see the enjoyment he gets from playing, and that's such an important quality."

Petta knows from painful experience the fun can be kicked out of any player if they are being lumped up and down the pitch by opponents who know of no other way to stop them.

Forrest already has the bumps and bruises to prove it's already happening to him. But Petta warns opponents they are wasting their time adopting such tactics.

He explained: "I have no fears about James being able to stand up to any physical treatment which he receives on the pitch from opponents who can't stop him any other way.

"We've already seen he can cope. And, with the experience of the past two years under his belt, he will be smarter and will know better how to avoid the fouls."