Shane Williams has raised the thorniest issue facing Wayne Pivac two years out from the next World Cup as the legendary wing predicts the Wales team will undergo a revolution ahead of 2023.

The big question for Pivac is whether to try to push through to France with the golden generation of 30-somethings who have brought Wales so much success over the years.

The alternative involves accelerating the development of the next generation.

Read more: For the latest rugby news and interviews, stop by our home of Welsh rugby

There will be clues as to Pivac’s thinking on the matter when he names his squad shortly for Wales’ autumn programme of matches.

Still the top-performing players in their positions, the likes of Alun Wyn Jones and Ken Owens, plus Jon Davies, who had a fine game for the Scarlets on Saturday evening, seem highly likely to be in the coach's opening panel of the 2021-22 campaign.

But Williams has pondered a significant poser for Pivac.

Saying he’d like to see more youngsters pushing to be regular starters at regional level and beyond, Wales' record try scorer asks in The Rugby Paper : “Should Wales be relying on all their 30-somethings two years out from the next World Cup or investing two years of international experience" in younger players?

He goes on to name a glut of younger stars Pivac potentially could fast-track through for the World Cup.

Dragons pair Ben Carter and Aneurin Owen are among them. Only this week, a Rodney Parade source said of lock Carter: "He is a wonderful prospect, a youngster who listens and does everything as it should be done. He's humble and never gets above himself.

"His potential is huge."

Centre Owen is similarly well thought of, with the 20-year-old offering something different with his footballing skills.

Pivac's challenge is to work them and others into the set-up without over-exposing them. In Carter's case, that means being part of squads and learning off the likes of Alun Wyn Jones.

The captain is showing no sign of wanting to call it a day, and while he is at the top of his game, the expectation is Pivac will continue to pick him, it not being especially clever to needlessly ditch that experience, leadership and quality.

The same applies to differing degrees to the coach's other senior statesmen.

That said, unless Pivac acts it could mean Wales journeying to France with a squad that has a lot of miles on the clock.

“We could do to France with a great team on paper, but with a completely different age profile to most other sides," continued Shane.

“At their best, this Welsh team could take on any side in the world: Liam Williams; Louis Rees-Zammit, George North, Jonathan Davies, Josh Adams; Dan Biggar, Gareth Davies; Wyn Jones, Ken Owens, Tomas Francis, Adam Beard, Alun Wyn Jones (capt), Josh Navidi, Justin Tipuric, Taulupe Faletau."

But he said 'the problem is of those names mentioned above, only three will be under the age of 30 come the next World Cup in France.'

The three in question are Rees-Zammit, Adams and Beard.

Other youngsters Williams lists as being among those Pivac could invest international experience in heading include Leicester Tigers openside Tommy Reffell, Scarlets wing Tom Rogers and Ospreys hooker Dewi Lake.

“While there will be other fresh faces to be considered, there is no doubt the team will be going through something of a revolution in the next two years," says the 91-cap former wide-man.

Pivac is going to need great judgement to handle the issue.

Wales had to do without many of their seasoned brigade in the summer and came unstuck against Argentina. In some cases, young players are still a long way short of those of who've been in the set-up for a long time.

Doubtless, Pivac would want to introduce new faces gradually rather than oversee huge selection upheaval during the next 24 months.

Former Wales wing Shane Williams

And Williams hasn’t even named Leigh Halfpenny in his deliberations.

One of Wales’ greatest goalkickers and full-backs, he is sidelined by injury but has made clear he still has plenty to achieve in the game. Presumably, his goals will include making it to the next World Cup if possible and also completing 100 appearances for his country — he needs four more caps.

It hard to imagine there would be a more popular century.

Pivac, of course, can’t afford to let sentiment come into it, but if Halfpenny and others of his age bracket are playing better than younger rivals it would be difficult to justify leaving them out.

Such are the choices that will face Wales’ coach over the next couple of years.

To get the latest Welsh rugby news delivered straight to your inbox, you can sign up for our Welsh rugby ne wsletter.