JONNY Hayes pretty much nailed it when he compared his Celtic captain Scott Brown to Benjamin Button, the fictional F. Scott Fitzgerald character who gets younger as he ages, as he chatted to the media after a game at Parkhead earlier this month.

Brown is 34 now, but is as every bit as fit and strong, possibly more so, than he was when he first broke through into the Hibernian side as a callow kid of just 17 way back in 2003.

His outing against Livingston at Parkhead on Saturday – a match which he scored in as the home team eased to a comfortable 4-0 win that maintained their lead at the top of the Ladbrokes Premiership – was his 27th of the 2019/20 campaign.

READ MORE: Celtic captain Scott Brown refuses to rule out second Scotland comeback at Euro 2020 finals

But it looked, as he bounded around the slick Celtic Park turf with all of his usual energy and enthusiasm, as if it was his first.

There is, though, a very good reason that “Broony” is still performing so consistently for Neil Lennon’s men both domestically and in Europe; he is no longer playing for Scotland.

Would he be available for selection every week if, as now looks a possibility, he was to come out of international retirement and help the national team in the Euro 2020 play-offs in March?

Would he be able to dominate games to the same degree next term if he represented his country in the tournament proper in the summer?

Brown has repeatedly defied those who have predicted his career at the top level was finished in the past few years and, what is more, has taken great pleasure in doing so. But he would be risking his ability to compete going forward was he to try and add to his 55 caps.

At the same time, he would jeopardise Celtic’s attempt to win their record-equalling ninth consecutive Scottish title and, if they beat Rangers to the league trophy come May, their tenth next season.

It is a minor miracle that he has been playing as well as he has in the Premiership, Betfred Cup and Europa League as it is given the already excessive demands on his body.

The rests which he has had during the international breaks in September, last month and this month have been invaluable to him and have played a huge part in ensuring he has avoided picking up problematic strains and niggling injuries.

READ MORE: Neil Lennon: I wouldn't be surprised if Celtic captain Scott Brown received a Scotland recall

That wasn’t the case back towards the end of the 2015/16 campaign when Brown appeared to be a spent force. He struggled badly in the William Hill Scottish Cup semi-final against Rangers at Hampden which Ronny Deila’s side were outplayed in and lost on penalties.

The complete break which he had from football that close season – the first since he started playing professionally some 14 years earlier – and the arrival of Brendan Rodgers as manager revitalised him. He hasn’t looked back since.

Going back to international football in a bid to realise his long-held ambition to play in the finals of a major tournament would be a retrograde step for a man who could, if he is smart and sensible, conceivably play on until he’s 40.

Being able to turn to Brown in the meeting with Israel next year may well be appealing to Scotland manager Steve Clarke despite the wealth of talent he currently has at his disposal in the midfield areas.

If the national team safely negotiate their last four tie then the experience, combativeness and defensive nous of such a seasoned campaigner would be invaluable against either Norway or Serbia away.

The same goes for the finals when Scotland are guaranteed to come up against some of the best teams on the planet.

Callum McGregor, Ryan Jack and John McGinn, as no less a judge than Steven Gerrard pointed out on Friday, quickly struck up a good understanding in midfield and performed well together in the Group I wins over Cyrpus away and Kazakhstan at home this month.

Clarke could do worse than field the same trio, if they are fit and available, once again in Scotland’s next game even if Kenny McLean of Norwich City and Scott McTominay of Manchester United are in his squad.

Still, the temptation to turn to a fine footballer and huge personality like Brown, who he has spoken to about returning since he succeeded Alex McLeish as manager back in May, will doubtless be great.

READ MORE: Alison McConnell: It might be unpopular but if Brown wants a Scotland recall he should get it

But what shape will the midfielder be left in if he does? It is, impressive specimen that he is, difficult to see him skipping back in to Lennoxtown ready to resume club duties after being involved in physically demanding and mentally draining internationals.

Neil Lennon admitted he will have a chat with his skipper about his intentions if Brown declares himself available. The Northern Irishman, who was able to prolong his own club career after bringing an early end to his own international playing days is sure to warn him of the dangers to both him and Celtic going forward.

Lennon is well covered in central midfield with Nir Bitton, Ryan Christie, McGregor and Olivier Ntcham all capable to playing there. But none of them have the presence of Brown. Not having his talisman would be certain to have a detrimental impact on performances and results.

AND ANOTHER THING

Oliver McBurnie will be doing well to dislodge Steven Naismith from the Scotland team come the Euro 2020 play-offs given how well the Hearts man acquitted himself in the wins over Cyrpus and Kazakhstan.

Still, it was nice to see the Sheffield United man pop up and score a last-minute equaliser against Manchester United in their Premier League encounter at Bramall Lane last night.

McBurnie might not have scored for the national team in his nine appearances to date, but no player who operates at such a high level should be written off.