As a doctor, sports enthusiast and parent, John "Doc" Mayhew has evaluated multiple codes in New Zealand from front row seats.
He has had roles with the All Blacks and Warriors, worked at the Commonwealth Games and with New Zealand squash and cross-country teams. Sir Clive Woodward once courted him to work at English Premier League football club Southampton.
All that has fitted around his work as a GP and clinical director at Sovereign Insurance. Time to sit back then and wind down after about three decades patrolling the sidelines?
It will happen but Mayhew does have one itch to scratch which has no pharmaceutical solution.
He's been fascinated with cricket since he played as a youngster and would love to tour with the New Zealand side, especially through India and Sri Lanka.
"I'd almost do it for nothing," he told the Herald.
"If I had one dream job, I'd love to work with New Zealand Cricket. It's a game I really enjoy. I would be interested in the challenges of going to places like India, where cricket is really huge."
One of the confronting chapters for Mayhew as he juggled his burgeoning sports medicine career was helping Jonah Lomu through his All Black career and then being summoned when the 40-year-old died suddenly last year.
"I still find it quite hard to deal with. He was a good friend and obviously there have been some off-field issues subsequent to his death which haven't helped him or his memory a lot but he was a great person and obviously a fantastic player.
"He was a player where EPO, which has been used in cycling and other endurance sports illegally, was designed to be used by people with chronic renal failure. We never used it with him and, as a consequence, he was always on two of four cylinders, or four of the six cylinders.
"He was most probably the strongest player that I knew playing for the All Blacks, explosive for a guy of 120kg. Over 10-20 metres, he was quicker than anyone.
"He was remarkable getting those levers moving so he could beat a player by running around them, through them, over them, throwing them out of the way, and we most probably didn't see enough of him at his peak because of his medical condition."
Not many people on renal dialysis fly internationally but Lomu was able to arrange treatment and complete it. There was a risk and Lomu was aware of that but he had appropriate dialysis during the World Cup.
He had stopped off in Dubai on the way home for more dialysis and was due to have more when he got home. People in renal failure had more risk of thrombosis and cardiovascular disease and Lomu was aware of that.
"Should he have done it? He would have done it anyway," said Mayhew. "He made an informed decision and we weren't expecting it to happen."
Mayhew did not anticipate his career would take the course it has either but after travelling to the UK for a post-grad sports medicine course, he hooked up with the fledgling North Harbour Rugby Union.
In his spare time, Mayhew locked the Northcote scrum and during one injury-ravaged Harbour tour was strong-armed into being a loose-forward reserve against Otago. As teammates threatened to fake some damage, Mayhew fretted about going up against Brent Pope, Paul Henderson and Mike Brewer.
Situation averted, Mayhew took the No19 jersey home and retired from provincial rugby.
The "Doc" and "Abo" provincial partnership transferred to the All Blacks as Mayhew and physio David Abercrombie took their expertise to the international stage. The pair trained with the squad as 26 players got through two games a week.
There was a small management crew which has mushroomed to the squads and staff today who prepare for one match a week.
There was a risk of excess as teams looked for one per cent gains and they had to be careful not to get bogged down in gimmicky stuff.
"I think sports science has a huge role to play. A good coach uses sports science appropriately, like video technology, which means all the players have GPS and at training we know how far and how fast they run. It's useful and how we use that information is crucial," he said.
Mayhew does not subscribe to the good old days theory. Sports grounds, facilities and preparation were all a step up from what they once were, although he does have one lament. He wishes rucking still featured in rugby.
"It was a safer game, believe it or not. It was a lot busier for me post-game sewing up people but the breakdown in rugby is still a problem," he said. "It is a huge collision area. Injury-wise, it is like rugby league tackling after they have been tackled. There are big hits [in league] but once that's been made, they are finished.
"In rugby, you are held up and some other clown smashes you and that's a real worry in terms of knees and things like that. I think in rugby, the number of collisions is more than league."
Mayhew accepts he may be naive but does not believe performance-enhancing drugs are a problem in rugby and league but is wary of their intrusion in athletics, swimming and power sports around the globe.
It was a blight on sport and the World Anti-doping Agency (Wada) were doing their best to combat the curse as athletes and drug scientists were usually a step ahead because growth hormones were hard to detect.
Detection in New Zealand was tracking well and testing was rigorous in rugby and the NRL. Mayhew wasn't sure players were smart enough to evade those systems if they were playing every week.
However, they do not escape some serious injuries. He oversaw treatment for Michael Jones and Ruben Kruger who suffered serious injuries in tests while another equally severe involved his younger brother, David, who had a fractured dislocation of his ankle poking through the skin.
Mayhew is concerned about what the players of today will do once their careers are finished.
When he started, the All Blacks had careers outside rugby and Mayhew worried about life after sport now for those who went straight from school into pro rugby or league.
"They can't all be media commentators and coaches."