As Brad Thorn gets ready to write another chapter in his remarkable career it's worth wondering whether Mr Invincible is a one of a kind, or a sign of the times? TOBY ROBSON investigates.
Bigger, faster, and stronger - it's a wonder any professional rugby player lasts more than a handful of seasons before terminal injury strikes.
Professional rugby players' representatives love to say how short their client's careers will be - usually while negotiating for a pay rise.
They operate in an increasingly brutal arena, one tackle away from enforced retirement.
The average size of an All Black forward increased from 100kg to 113kg since rugby went professional in the mid-1990s and the backs have ballooned from 82kg to 94kg.
Collisions are now compared to car crashes. Concussion has become an unwelcome theme.
So what does it mean for the modern player's career span? And how on earth do you explain Brad Thorn?
The truth is professional sport has long been sprinkled with men and women who have somehow evaded both injury and the relentless pursuit of Father Time.
Thorn will turn 40 next February as he throws his Terminator-like body into a gruelling European season after signing a one-year deal with Leicester.
It will be big Thorn's 22nd season as a professional athlete since he joined the Brisbane Broncos way back in 1994. His feats and success are staggering no matter how you spin them.
In his trademark husky voice, Mosgiel's most famous export has often talked about his rigid routine of stretching, lifting weights and staying off the alcohol when asked about his durability.
''I'll do three half-hour sessions [a day]. It's time consuming and it's not much fun,'' he said a couple of years ago before offering a simple equation on why his bulky muscles have been an added bonus.
''You generally come out in better shape than the guy who is taking you on.''
When Thorn played the last of his 59 tests for the All Blacks in 2011, he was 36 - the second oldest man to be capped for the world's most famous rugby team.
Only Ned Hughes, an Invercargill hooker, has been capped at an older age, 40-years and 123 days, when he played against South Africa in 1921.
Interestingly, the average age at which an All Black has played his final test, has changed very little since 1900.
In the decade between 1900-1909 the average age at which an All Blacks test career finished was 26.9 years.
It would duck and dive slightly over the next 100 or so years, but in the last fully measured decade, 2000-09, it was 27.3 years, a difference of less than a year.
Rugby's closest comparable code, rugby league, has had its ageless wonders too.
Historians could compare Thorn to Billy Wilson, a front rower who played 20 seasons of first grade with St George and North Sydney from 1948 to 1967 before retiring from first grade at the age of 40.
Manly's Steve Menzies has been the modern era equivalent. He was 39 when he played for the Catalan Dragons in France last year and 40 a few months later when he played for Manly at the NRL Nines in Auckland.
Of course there are plenty of rugby players whose careers have been cut short by injury, but in the modern era there are a number of factors working in their favour.
Auckland based sports physician Mark Fulcher has seen first-hand how the brutal demands of professional sport can shorten an athletes career.
Currently the All Whites team doctor, Fulcher's worked with the Counties-Manukau Steelers and New Zealand's Olympic teams in 2008 and 2012.
However, Fulcher believes those lucky enough to dodge serious injury are hanging in a lot longer due to the financial incentives on offer across many codes.
''In the past people weren't making much money, so there was a desire to go do other things. If you think about Brad Thorn who is off to Leicester, of course he has the desire but I'm pretty sure he'll also be on pretty good money there,'' he said.
''If you think about rugby players what they are earning isn't generally enough to just set them up for the rest of their lives. They live a comfortable lifestyle and might have a property and some money in the bank, but they'll probably have to work again.''
Hence, the incentive to keep playing for a high salary remains high and statistics back Fulcher's hunch.
While the previously mentioned average age at which an All Black played his last test remained relatively steady, it spiked in the 1990s when the game went professional to an all time high of 28.7 years.
Notably a number of current All Blacks are well past that age and still showing no signs of stepping aside suggesting the average for the current decade from 2010 could eclipse those before it.
Fulcher said sports science and man management were undoubtedly aiding the older athlete.
''If you look [at Alessandro] Del Piero in the A-League for example, we are definitely getting better as an industry at managing these guys and extending their careers if they want to,'' Fulcher said of the 39-year-old former Sydney FC forward.
''More thought goes into training loads, guys who are getting older or might have a chronic injury, most clubs will have an old man's club. The first couple of sessions after a game they do all their training on a bike, so there isn't as much on the grass training.
''Toward the end of the week they might train with the team once or twice, but the overall loading is not as great.''
That's backed up by New Zealand Rugby Union senior scientist Ken Quarrie who has been a leading force in changing the game's attitude toward injury at all levels.
Quarrie helped drive RugbySmart, a joint initiative between the NZRU and ACC to educate coaches at all levels about injury management with the aim of reducing chronic injury and keeping players in the game for longer.
He notes the early furore in New Zealand rugby over the advent of rotation has subsided with the practice of managing player workloads now commonplace in provincial, Super and All Blacks rugby.
A paper penned for the NZRU by Quarrie in 2006 studied the Bledisloe Cup from 1972 to 2004 in a bid to chart the changing demands of the professional game on its athletes.
Its found rule changes during the 1990s such as the use of non-injury replacements, the use it or lose it rule at rucks, and an increased number of reserves had created the need for bigger and stronger athletes.
Interestingly, the paper ended by suggesting future research would be needed into how the changes would impact on the length of professional players' careers.
There still isn't a lot of raw data in rugby on that subject but Fulcher believes New Zealand's contact sports would do well to look to football for some answers.
A recent paper called FIFA 11 + studied 3000 men's players in Europe and provided conclusive evidence that the risk of major injury can be severely reduced with little effort or cost.
''I've found people who have a longer career tend to be the ones who did not get a major injury early in their career,'' Fulcher said.
''It's very rare for someone who tore their ACL as a youngster to still be around 10-15 years later, because they just aren't physically able.
''An example would be [netballer] Irene van Dyk. If you look through her career she basically never got injured, so in her 40s she's still in pretty good nick. She didn't have a grumbly knee that a lot of footballers or rugby players might have had at 22 or 23.''
Thorn - like the All Blacks' other seemingly indestructible player of modern times Ma'a Nonu - has a rigid daily routine and Fulcher believes that's a key component to longevity.
''There is compelling data about injury prevention if you do a couple of sessions per week doing the right thing,'' he said.
''The average guy can do 20 minutes, twice a week and reduce his risk of ACL rupture by 50 per cent and injury across the board by 30 per cent.''
With the direct cost of ACL injuries in terms of loss of income and future problems about $50 million a year, Fulcher believes following FIFA's guidelines could save the country $25 million a year.
''The uptake in New Zealand is not as high as it should be because there is still all of old school thinking.''
Fulcher, a goalkeeper for Waikato FC, said football tended to invest more heavily in injury prevention because of its sky high salaries.
''For example in the Champions League in Europe the opportunity cost of the average player for a month costs the clubs 540,000 euros.
"If you look at Super Rugby it probably costs $10,000 a month, which is still important, but not quite the same financial driver.
''It's important in rugby because the evidence is careers are likely to be shorter as it becomes exponentially more brutal.
"If you look at the All Blacks who won the 1987 World Cup versus the 2011 All Blacks the difference in body weight is about 20kg per player, it's astonishing.
''So I'd think the average player will have a shorter career, but the ones who are lucky and look after themselves can have a much longer one.
"Brad Thorn is an example of that but he's a bit of a freak."
- The Dominion Post
Who was the best-performed All Blacks forward on the northern tour?