Joe Schmidt (left) and Vern Cotter (right) enjoyed great success together at Clermont before Schmidt's departure for Leinster

Six Nations: Ireland v Scotland Date: Saturday, 19 March Venue: Aviva Stadium, Dublin Kick-off: 17:00 GMT Coverage: Live on ITV, BBC Radio 5 live Sports Extra, BBC Radio Scotland, BBC Sport website and BBC Sport app, plus live text commentary.

When Jamie Cudmore says Vern Cotter made him not just a "better rugby player" but a "better man" then you have to look to his back story to figure out what he's talking about.

We return, initially, to Clermont, where he was Cotter's second-row enforcer and one of the bruisers who finally got the club over the winning line in the French championship for the first time in their history, in 2010, after losing in the finals of 2009, 2008 and 2007.

Cudmore talks about Cotter's vast influence and, in turn, the influence of his assistant in France - Joe Schmidt.

If we're looking for somebody to chat about the rival coaches in Dublin on Saturday when Ireland meet Scotland then Cudmore is as good a man as any - and better than most.

"I was at the club from 2005, a year before Vern came and then a year and a bit after that Joe arrived. And that was the start of something very special for all of us."

Cudmore is a Canadian monster with a penchant, in the past, for on-field thunder and occasional bouts of violence. He's a strange contradiction; a beast on the rugby pitch and yet a gentleman off it.

That line about Cotter making him a better man? Well, to understand it we have to go back a little further, to Cudmore's early life in Squamish in British Columbia where in his late teens he got involved in the drug scene, collecting money for dealers and then getting done for assault, an offence that saw him spend his 18th birthday in a juvenile detention centre.

Jamie Cudmore played under Cotter and Schmidt at Clermont

Things got worse in the years after. When a neighbour came round to investigate the noise coming from a house party Cudmore held, he was beaten to death by two young men hanging around the scene.

Cudmore needed to leave this life behind - and he did. He moved to West Vancouver to play rugby, then to New Zealand and onwards to France. He spent two years at Grenoble then surfaced at Montferrand - or Clermont as they are now known.

'Huge respect'

"We became very close, Vern and me," says Cudmore. "He's a great family man. A country boy like myself. He comes from a small farm in New Zealand, likes to go out for a hunt, enjoys a good chunk of meat and a nice bottle of red wine. He's a simple man and extremely passionate about rugby.

"After working together for nine years we developed a great relationship. He helped make me a better man. He helped me when I needed help, supported me when I got into a bit of trouble, developed me in lots of ways. I have such huge respect for that man I couldn't tell you."

The pre-Cotter Clermont were doing okay and nothing more. They had many internationals in their ranks, many marquee names, but they were inconsistent. They could be sensational and they could be rank; you never knew what was coming next.

Schmidt's Ireland comfortably beat Cotter's Scotland at Murrayfield to clinch the 2015 Six Nations

"We had an amazing amount of talent but there wasn't much direction in the group," adds Cudmore.

"It was known as a team that had enormous potential, and money, but didn't have anybody at the helm who was guiding the ship properly and making sure everybody was on the same course.

"We had a fine collection of individuals but we weren't a team. Before Vern arrived there was a lot of frustration at the club because some of the guys were just floating along. If things were going well, they'd perform well, but if things weren't going well then some would just roll over and die.

"I knew nothing about Vern before he came. I didn't know about Joe either. They knew each other from coaching together at Bay of Plenty in New Zealand but I didn't know any of that back then."

'A fantastic foil'

He was to learn soon enough.

It was instructive to hear both coaches on Thursday as they named their teams. Cotter was asked about Schmidt and Schmidt was asked about Cotter and the differences in their personalities was hilariously evident.

Scotland have recovered from defeats to England and Wales with victories over Italy and France in the Six Nations

Cotter kept it brief and almost inaudible. That's just the way he's made. Schmidt, meanwhile, spoke at length, almost eulogising the man who brought him to Clermont. It was barnstorming stuff.

"I just found that he was a fantastic foil for me and that we actually enjoyed each other's company and that we offered different things to the team as far as coaching was concerned," said Schmidt.

"I learned so many things from him, just about being decisive, just about trying to grow the key leaders in a team if you're going to have a strong decision-making group on the pitch.

"I just found that he had a real ability to crystallise messages and deliver them. He drives an environment. 'Les yeux de glaces' was his nickname in France - the eyes of ice.

"He didn't have to say too much for you to know he was unhappy. I think that his presence is such that he does certainly drive a group incredibly well.

"You spend a fair bit of time coaching together, you pick things up and you probably don't specifically say, 'Oh, I learned that today'. They just merge as part of your coaching character because you've absorbed lessons from other people. I absorbed a lot from VC."

Ireland routed Italy in their last outing but have lost to England and France and drawn with Wales

Cudmore laughs at the mention of 'les yeux de glaces', saying: "Yeah, and you guys call him Stern Vern, right? It's kinda the same thing, really. Vern created that atmosphere where we wanted to out-work the other teams and be difficult to play against while also playing good rugby.

'A great combination'

"When Joe came in you could tell that they were different personalities but they were driven in exactly the same way. Joe was a classic teacher and knew how to dissect rugby and pick plays apart and make sure everybody was focused and precise about their role.

"Joe was the good cop to Vern's bad cop. Vern was the sledgehammer and Joe the surgeon's scalpel. Together they were a great combination.

"Some of the sessions were horrific. We went on a training camp to Corsica once. On the second night we went out for dinner and there was a bottle of wine between four people at each table. I don't know if it was a test or not. I'm not sure whether we were supposed to leave it unopened, but we drank it. Couple of glasses each. Nothing major.

"Vern and Joe killed us the next day. The fitness session was brutal. The boys were hanging on for dear life. You'd have thought that we'd lost by 50 points and then gone on a bender. The message was, ' Yeah, fine, let your hair down a little, but don't forget why you're here'. It bred mental strength and it forged a fantastic spirit.

BBC Scotland's Six Nations Extra

"It was difficult at times. A lot of guys fell by the wayside because they couldn't cut it. With Joe, the devil's in the detail. His attention to detail was unbelievable and it made the difference in 2010 when we won the league.

"We'd come so close so many times before (the previous three finals were lost by nine points, six points and five points) but we kept coming. Those two really strong leaders saw the problems and found the solutions and pulled us forward."

Cudmore is still in France, still at Clermont and still playing, when not injured, despite his 37 years. He is taking some first steps into coaching with his native Canada and says in Cotter and Schmidt he has years of learning at the hands of two masters.

Who's he rooting for at the weekend? "I'm staying out of that one," he laughs.

"All I'll say is that those guys created Clermont as we know it and I'm not surprised in the slightest at Joe's success at Leinster and Ireland and I'm not surprised either that Vern looks to have turned things around with Scotland. You've got two majorly impressive men there."

A reunion, of sorts, is almost upon them.