He had a big impact on Ruben Wiki's career, almost brought Richie McCaw to his knees and from tomorrow will be dishing out the pain at the Warriors.
New head strength and conditioning coach Carl Jennings clocks in for duty as pre-season training gets under way at the Auckland club this week.
Jennings, who has previously worked at Bradford, Canberra, Penrith and the Crusaders, is the man the players will love to hate.
"I've got lots of psychotic routines," laughs Jennings. "It will be hard work from day one but nothing worth achieving is achieved without hard work. When they run out on day one, they are going to look lean and mean and are going to be fit without question. I'm not bagging what has come before me - I'm drawing a line in the sand with my vision about where these athletes need to be."
Like everybody else in the NRL, Jennings recognises the immense physical potential of the Warriors, particularly the current group that enjoyed such success in 2011.
"They are tremendous natural athletes, tremendous natural ball players and tremendous in terms of speed work," says Jennings. "This is a special group with some really special talent. But the world is full of talented underachievers, so we have to create an environment that allows them to thrive and feel inhibited to play the style of football that they want to play - and what Matt [Elliott, coach] is going to facilitate them to play."
Jennings' chief lieutenant will be Ruben Wiki, confirmed as strength and conditioning coach last week as part of a bolstered five-man team that also includes former MMA fighter Brad Morris. It could be seen as something of a reprieve for Wiki - he struggled in a part-time role as defence coach last season - but he is hugely respected and had success in previous training roles.
Jennings has a long association with Wiki, going back to the Raiders at the turn of the last decade. He developed the 'Wiki blitz', a mini-training programme so harsh in its intensity it tends to be talked about in hushed league circles.
"Ruben came to me and wanted something just for him that prepared him for battle," explains Jennings. "We developed something that he could do after the last training session of the week, usually on Thursday afternoon."
'The Wiki' combines rowing, burpees and a clean and press weights drill and tests aerobic, anaerobic and alactic systems. It starts with 1000m on a rowing machine, then 10 burpees and 10 clean and press. Then an 800m row, 12 burpees, 12 clean and press (with 50kg), 600m row, 15 burpees, 15 clean and press, 500m row, 18 burpess, 18 clean and press, 400m row, 20 burpees, 20 clean and press, and ends with a 300m row.
Performed continuously, Wiki's record of 18m 40s has rarely been challenged, though many have tried. Jennings used the exercise on the Great Britain team in the mid-2000s and recalls only "one or two" managed to break 20 minutes.
"We started with Ruben and then everyone else in the team wanted to do it," says Jennings. "We also used it at Penrith and even the Crusaders felt a bit of Wiki-love at certain stages last year. It's not the be-all and end-all but it's a very useful tool."
Working with Richie McCaw, Jennings also developed the 'Richie blitz' as an endurance tool at a time when the Crusaders captain was restricted in the amount of running he could do. It sounds eye-wateringly tough.
"You do maximum effort on the rower for a set time, then come back to maximum effort on weights for a set time, then swap again. Essentially, you are going to the point of total and utter exhaustion and maintaining it for an hour.
"The 'Richie blitz' is pretty insane but very few since have been able to complete it. In terms of toughness, they [Wiki and McCaw] are very similar kinds of characters and they do whatever is needed to win."
Jennings, A former Great Britain shot put champion, met new Warriors coach Matt Elliott "by chance" and was appointed head trainer at Bradford soon afterwards in 1996. The duo have worked together for most of the past 17 years, though their approach has not been without its critics. Particularly at Bradford and Penrith, there was a perception that they had a heavy emphasis on bulk and power, turning their forwards into fearsome (but slightly immobile) monsters. It is an approach that has been tried before at the Warriors, especially in 2004, and the results were disastrous.
"Looking from the outside in, you can have that perception," says Jennings. "We had a lot of success a thousand years ago at Bradford and at that time strength training was all new. My background was a strength and power background and that is what I knew. People say that I have always developed big sides but at the Canberra Raiders, we had a small side that was super-fit. We had a team that loved golden point scenarios, loved to get in a shit-fight because we could win those games, as we were fitter than everybody else."
Jennings wants people to judge him on results but offers assurances that he is not aiming to turn the Warriors into a bunch of monoliths.
"It's a bit unfair to get transfixed on size and bulk with me," says Jennings. "I've always got the best out of the players I've had in front of me. If people think that I am going to put size and strength on players for the sake of it, they are pretty deluded, to be honest. I've got a lot of size and strength [here] and in some respects, I am going to get them a lot more leaner and fitter. The mantra is fit; conditioned; tough. My vision is to enable these players to play 100 miles an hour in every game and they need to be conditioned, fast, mobile and functional athletes."
Alongside Jennings and Wiki will be Morris, Dayne Norton and Adam Sadler. Morris, who worked at Penrith in 2010 and 2011, is the sports science manager but will also add value as wrestling coach - having fought in the Ultimate Fighting Championship (UFC) in North America. Norton, a long-time Warriors and Kiwis trainer, will be rehab and speed coach, while Sadler is the team's performance analyst.
"I've got a narrow focus," says Jennings. "I need to understand Matt's vision and then my focus is to develop the world's greatest rugby league athlete and I am going to work towards achieving that. I won't leave a stone unturned until they achieve their potential which is, to be honest, limitless. People have spoken about it for a long period of time but I think we are really going to have a crack at it this time ... I really do."