Speak to any Australian footballer who has ever worked with strength and conditioning coach, Andrew Clark and they will all tell you the same thing - he is the absolute best in his field.
Back in 2015, Graham Arnold credited the sports scientist for bringing him “sanity, balance and clarity” and said he was “one of the best blokes I've ever met in my entire life.”
Repeat these sentiments to Clark and he’ll admit that it’s nice to hear these things but it’s not where his greatest satisfaction lies - it’s making players feel “bulletproof” that drives him.
A former player himself, the Gosford-born product has carved out a career as Arnie’s right-hand man in the Central Coast, Japan, Sydney and now the globe with the Socceroos.
Humble, easy-going and highly intelligent, I caught up with ‘Clarky’ to reflect on his ten-year “marriage” with Arnie and if they’ve had any bust-ups, why his exposure to ethnic influences in football were “wonderful” and if he’s ever been tempted elsewhere.
LZ: First and foremost, I want you to take me back to your playing career. You had stints in the National Soccer League, Hong Kong, Malaysia and with the Central Coast Mariners where you ultimately retired. What are some of your memories from those days?
AC: I think my love of football started long before those days and I guess we’re all touched by certain coaches as we’re developing that inspire you in the game and to develop a love of football.
I came from a sporting family that were swimmers, believe it or not. They really had no history or no interest in football at all but it was something that I loved from the start.
Being a bit of a late developer physically, I was always trying to catch up and I maximised everything I had which was physical quality. I was constantly trying to become a better footballer, right until the backend of my career at the Mariners - if you want to call it a career! [Laughs]
It was an amazing thing for me because I'd been away from home for nearly ten years and then all of a sudden right at the end of my career, the A-League had finally formed with a team that was going to start in the place that I grew up.
I spent nine years there and had the opportunity to play and take on the strength and conditioning role. It was so nice to play in front of my family but it was also a soft landing in the business of sports science and strength and conditioning which I'd already been doing a lot of along the way.
My home club gave me the opportunity to develop and then grow out of that area into the next few steps which have led to where I am now. 
You completed a Masters in Sports Science ten years ago now - what are some things you’ve learned about Australian football?
Tactically we're a lot smarter in the A-League now than we were back then.
I think Asia actually put us in a position where it's not good enough to just match a team physically - we need to smarten up and be able to compete, especially given the other factors that make the environment difficult like the salary cap and the travel demands.
I'm heavily involved with all of the national teams - from the Under 16s trying to qualify for the next Under 17s with Trevor Morgan to the Under 17s going to the World Cup, to the Matildas.
I think there are some really great technical players coming through at that younger age group and it's our responsibility to nurture that, identify the players that have the physical qualities to be top players and then provide them with a pathway to play at the top level in Europe.
That gap where players just stop playing games has hurt generations in Australian football.
Everybody in football knows that if you're not playing matches, your development stops no matter how much training you do so these kids need to play - they’re desperate to play games.
The fact that Trevor has got his team and they're about to compete in the World Cup is a great feat but kids measuring themselves up against the world has to happen in every age group. Then they need to be exposed to playing senior football as quickly as possible.
I want to pick up on the point about the technical ability of these young players coming through. There's this theory doing the rounds suggesting that we're producing athletes and not footballers nowadays. Does that resonate with you?
I don't really think about it too much, to be honest. I came through a period when I was young where I was first exposed to the influence of the ethnic groups in Australian football and it was a wonderful influence.
Most of the people that were coaching us really knew what professional football was about because they had either played in Europe and then come as migrants or they were first-generation and their parents were professional players.
Then there's a whole period where, as a nation, those people naturally got older and they became less influential in the game.
Now, you've got a whole generation of coaches trying to measure up to the things that those people taught players of that generation.
I think coaches in Australia are ambitious and we want to have Australian coaches coaching at the top level.
Below that top-level are ambitious young coaches and they're trying to upskill themselves through the people we have locally; through the internet, through watching everything that happens in the world and I'm no different to those people.
To become coaches that influence kids technically, to make sure that they're at a standard and they have the basic tools to be able to be professional footballers anywhere in the world - that's been a challenge for Australia.
From my experience, when you don't have those tools you will get to a point where you can't go any further. There are coaches out there that are doing a great job but the kids need to play and they need to play more as far as every day of the week.
Did you ever consider coaching?
I think I am a coach, to be honest. Without an understanding of how you want to play the game, I think it's very difficult to be very good at my job.
My job is looking at football from a different starting point but the end place needs to be how you want to play the game of football.
My, you could call it a marriage with Arnie, for ten years is about having some common ground on how we want the game to be played and that evolves.
The basic thing about the style of play is athletically demanding and that's where I fit in.
You’re looking at identifying, looking at helping to improve training, coaching players to be able to athletically carry out and sustain the style of play that we want to play.
But at the same time, having an understanding of how to keep those players healthy and how to expose their best qualities in a football context and I think that's the challenge in my job.
The responsibility I have in my role at the FFA is to try to help people in my part of the business be better coaches and have a better understanding of football and where they fit in.
It just so happens that for us at the moment it's tactical, it's athletic and it’s physically demanding so I’ve got a job to do. 
Back to your relationship with Arnie and the marriage as you referred to it. I want to know about those initial days when you first got to know one another and how the working relationship also came to light.
Lawrie [McKinna] was our coach back then and I spoke to him and said ‘look I'm finished now’ because it was actually the physical thing that stopped me.
I knew that I couldn't do the things which made me capable of playing the game and that was to outrun people. Physically I could just rob players until they either gave up or they got substituted and that was basically my game.
I had an existing contract that if I finished playing because I was already doing the strength and conditioning role in a part-time capacity, I could just continue on full time in that role and that was when Lawrie said ‘I am finishing as well.’
That’s when Arnie came in and we had kind of crossed paths but I didn’t have a previous relationship with him.
We sat down for a coffee one day before he went away for the World Cup and we had a chat and our beliefs pretty much aligned straight away.
At the start, I was doing a completely different role to what I do now. It went from a more pure sports science strength and conditioning role and then it evolved to taking bits and pieces of sessions and then working more in a football context.
We come from different starting places but the end position is exactly the same. We have to debate but in the end we have to agree and when we agree we get on with it, we get it done.
So now our families are close, we travelled away together and now we’re tripping around the world. It’s a good relationship and I'm very fortunate.
I only wish that someone like him came across my path at a really early stage in football because I see what he gives the players. They lean on him for life pretty much. When he’s touched a player, he's kind of a safe house for players.
I build similar sorts of relationships but he’s certainly a very good mentor to me and a good mate as well. 
Do you ever have any bust-ups?
Of course we do! You can't work so closely with somebody without disagreement but that's a healthy thing.
Any relationship that never argues is probably not a healthy relationship in my eyes because that’s when you expose your difference of opinion and you work through it.
If it’s a real relationship then you'll find a solution and the common ground.
The [bust-ups] are never serious that they would ever jeopardize our friendship or our working relationship but of course, we disagree on things - that's part of every single decision.
Have you ever been enticed elsewhere?
Many times! [Laughs] We've always spoken openly that if an opportunity came that was too good to refuse, that we would never stand in each other's way.
Arnie’s like that with all of his staff and he doesn't hold anybody ransom and I feel exactly the same for him.
If a massive club came along and they said ‘listen, it’s you and that's it’ and he couldn’t pass it up, we have an understanding that our paths at some stage may diverge and then come back together.
That’s just the part of the business that we're in.
It must be challenging not having consistent contact with the playing group. What do you do in between camps?
The national teams have been the most challenging thing that I’ve done so far because building relationships long distance is very difficult and you have to think of new ways to do that.
Since we started in the job, if you're just talking on a domestic level, we've got great relationships with the A-League clubs and we all have our own interests.
I would be disappointed in a club that wasn't looking out for their players for their club. Things like trying to keep that player or making things difficult purely because they want to win. I would hope that they would be disappointed if I wasn't doing the same thing for the national team.
But I don't think we need to compete. We need to work together to make sure that the winner is the player because if they get stuck in the middle, it’s a terrible situation for the player.
They often do though when it comes to international windows, don’t they? There seems to be quite the uproar from coaches here in the A-League when players need to be released to play for their country. What are your thoughts on it?
We need both. Without the Socceroos, without the Matildas, how do we know how we measure up in the world? If we're not allowing players to measure up against international competition, then how do they know how good they are and what they need to improve?
The people that often have the arguments, and I'm no different, they have reaped all the benefits of playing for Australia; they’ve played for junior national teams, they’ve played at World Cups and in their heart they know that, that has made them who they are today.
We need to work together but we need to decide that these kids playing for their country is important and it's important for the game and it’s important for the player.
It's important in the end for the Socceroos and Matildas, which the greater sporting community support with all their heart.
It doesn't matter what sport you love or play in Australia, when it comes to the Socceroos and Matildas and they’re playing international football - the country supports them.
So those young players need to grow and develop in the club and in the national team environment in as harmonious a relationship as possible so that we have a Socceroos and Matildas team that we can be proud of.
