Nathan Lyon reels in a Marlon

"How good would it be doing this full-time?"

That was the thought in Nathan Lyon’s mind as he was bowling to Australia's batsmen five years ago in the Adelaide Oval nets in between his duties as one of the historic venue's ground staff.

Just a year later, he was the country’s first-choice spin bowler.

Five of the best: Lyon's top performances in Baggy Green

Skip ahead an Olympiad and Lyon is still the premier spinner, playing his 50th Test match in the Baggy Green in Hobart this week, and Australia’s third-most capped slow bowler behind leg-spin legends Shane Warne (145) and Richie Benaud (63).

And his 175 wickets in that period are more than any other Australian off-spinner, a record that - much to Lyon’s chagrin - has his teammates calling him 'The GOAT' (Greatest Of All Time) whenever his record or status is raised.

Lyon in Kingston after becoming Australia's most prolific off-spinner // Getty

But if you ask the man himself, Lyon’s record-breaking achievements from turning a cricket ball pale in comparison to the friendships he's forged in his half-century of matches for his nation.

One of those friendships, in fact one of the closest and most treasured to the lissome kid from the country NSW town of Young, is that with Michael Hussey, who remembers a skinny off-spinner impersonating one of his future rivals during that net session back in 2010.

"First time I met him we basically dragged him off the roller at the Adelaide Oval when he was working there and got him to come bowl in the nets,” Hussey told cricket.com.au.

"We were playing against England and Graeme Swann was a threat and people in Adelaide thought he (Lyon) was a pretty good bowler so we should get him over.

"You watch him bowl in the nets and I faced him a lot in the nets, you already knew you had something pretty special there. But you never know if he was going to go on and play Test cricket."

Lyon made his domestic cricket debut less than a month later, opening the bowling for South Australia in a Big Bash Twenty20 match and staring down current Australia vice-captain and prolific NSW power-hitter David Warner.

NSW won that match as Warner made an unbeaten 73, but the Redbacks exacted the sweetest revenge a month later when they thumped the Blues in the competition’s final, Lyon playing an integral role with two scalps.

Lyon in his first season with South Australia // Getty

He finished the tournament as the joint leading wicket-taker alongside Pat Cummins, the young Blues fast bowler who was enjoying his own exponential rise up the ranks.

Within 12 months, both would make their Test debut.

That 2010-11 season also saw Lyon make his maiden first-class and one-day appearances for South Australia, impressing those in the know with dip and bounce he generated from spinning "up the back of the ball", a technique he developed with former NSW allrounder Mark Higgs during his days in Canberra.

An Australia A tour to Zimbabwe followed in the winter, where the 22-year-old topped the wickets tally in the 50-over format but couldn’t crack the red-ball team. It all made his selection in the Test squad to tour Sri Lanka, which was named just days after the conclusion of the A tour, more than just a shock. He was the definition of a bolter.

"Looking back at it now you can sit back and laugh," recalled Lyon to cricket.com.au of his first tour with the senior side. "When I was there (in Sri Lanka) it was the first real time meeting the likes of Michael Clarke, Ricky Ponting and Brad Haddin.

"I bowled to them half a year before at the Adelaide Oval, but I never really met these guys and the first time I met them was when the lift opened in the team hotel and I introduced myself.

"I grew up having their photos on my wall as a kid. That was pretty amazing meeting those guys (and) being in the squad was a dream come true."

Lyon and Ponting on the 2011 tour of Sri Lanka // Getty

The dream got better when Lyon was selected to be Australia’s 421st Test player in the first match of the series in Galle, receiving his Baggy Green from former Test skipper Greg Chappell. And if that wasn’t enough, his fantasies kept escalating when he captured his maiden Test wicket, that of Sri Lankan legend Kumar Sangakkara, with his very first delivery.

"I’m still a bit nervous and excited talking about it now," Lyon said. "It was pretty surreal to be honest. The way the Test was going I remember it was a drinks break and ‘Pup’ (Clarke) as captain said, ‘Are you ready to go?’.

"I said ‘oh well, I’ll give it a crack’.

"I remember ‘Punter’ (Ponting) came over just before my first ball and asked me how I was going.

"I said I was pretty nervous and he said ‘You’ll be right, just back your skill’.

"I actually thought that ball was really wide but I was lucky enough to have Pup there at first slip to take a pretty good catch."

Lyon was overcome with emotion with his maiden Test wicket, and Hussey was riding the high just as much as the bowler.

Upon assembling in Sri Lanka, then batting coach Justin Langer assigned each new member of the squad – Lyon, Trent Copeland and Shaun Marsh – a ‘buddy’ in the form of a senior player who could be called on at any stage to pass on wisdom, help with strategy or just have a chat.

Hussey was Lyon’s ‘buddy’.

"There were a couple of fresh faces in that Test squad,” said Lyon.

"I was the youngest one and with the least amount of first-class games played.

"Justin Langer spoke to Mike Hussey and to myself and said ‘Huss’ was my go-to man.

"Go knock on his door when you need to and since that day in Galle I was lucky enough to strike up a wonderful relationship with Mike Hussey.

"It really is a dream come true to be friends with him. He’s been a mentor to me and it’s pretty special."

Hussey and Lyon quickly formed a close bond // Getty

It’s a special bond that 18 months later convinced Hussey to anoint Lyon the new custodian of Australia's team song, 'Underneath the Southern Cross', which is belted out after an Australian victory.

Despite having played 19 of the 20 available Tests since his debut (he was omitted for a fourth fast bowler in Perth 2012), Lyon was at the time consistently under pressure to justify his place in the XI, which left Hussey’s choice of heir songmaster baffling to certain fans and pundits.

But Mr Cricket had no doubt about his successor.

"There were quite a few critics out there saying I shouldn't have handed it to him because he might not be around,” Hussey said.

"I had faith and belief in him that he could keep his place in the team and do well.

"My decision was based around character. I knew he had a really good character and I knew he had a good work ethic and great respect for the game, and he played the game for the right reasons as well.

"I thought those attributes he possessed would hold him in good stead for keeping his place in the team and performing well but also the character traits that I wanted to pass on to the team when I left."

Lyon had to wait 10 months to lead the song for the first time, and at more than one point he was in danger of exiting Test cricket without humming a single note.

The disastrous 2013 tour of India saw four players suspended, Australia handed a 4-0 series defeat and Lyon dropped on form for the first time in his career.

His absence lasted only one match, with the spinner returning for the final two Tests and claiming a career-best 7-94 in Delhi.

Next up were England in England, where Lyon had to hold off Pakistan-born asylum seeker Fawad Ahmed for the role of the No.1 spinner in the squad. Ahmed was included in the squad for the preceding ‘A’ tour, bringing with him momentum and history as he sought what would have been a remarkable Test debut.

But Lyon held firm while the cold climes of the United Kingdom troubled Ahmed and his loose grip on the ball. The leg-spinner was sent to Africa with Australia A and unknown youngster Ashton Agar was added to the 18-man Ashes party, seemingly in a support role to Lyon.

But as the first Test approached, coach Mickey Arthur was sacked and replaced by Darren Lehmann. Along with national selector Rod Marsh, the new coach handed the left-arm orthodox Agar a debut at Trent Bridge in order combat England’s top order packed with right-handers.

Agar’s deeds with the bat in that first Test will go down in Ashes folklore, but the 19-year-old's first taste of Test cricket was over after just two Tests. In his place came Lyon, who quickly proved his doubters wrong with three top-drawer performances in a losing cause.

Lyon and Agar during the 2013 Ashes series // Getty

Lyon hasn’t missed a Test since, and says getting dropped on the eve of the Ashes galvanised him to be a better cricketer and ensure it never happened again.

"It’s one of those ones when you always try and find that confidence,” Lyon said when asked when he felt comfortable in Test cricket.

"After the England Ashes (in 2013) and after that disappointment of getting dropped for the first two games, especially working in to a massive series, you’ve been planning it for a couple of years then to be dropped on the verge of that is pretty disappointing.

"But I was able to work my way back in there and I feel at the top of my game since that day.

"I’ve been lucky enough to work pretty hard with John Davison and really since being dropped and being recalled back into the team, that was the biggest thing."

Davison, Canada’s 2003 World Cup hero and former South Australian off-spinner, says he met a "wiry 18-year-old who bowled around himself a fair bit" on a state visit to Canberra working as a spin consultant for Cricket Australia.

It was there, like with Hussey in Galle, that an "unbelievable friendship" was sparked.

"He’s someone I trust a lot and (can) easily talk to about anything and everything, which really makes a good coach,” Lyon says of Australia's spin coach.

"He’s very good at what he does and there’s trust and honesty there in our relationship and I think that’s the biggest key with coaches.

"If you can have an open and honest relationship but also have that trust in each other that we’re working for the same goal, working in the same direction, that’s the main thing."

Davison says Lyon has the “perfect build” for an off-spinner; a “tall, wiry frame with long, strong fingers”. But even with the ideal physical mechanics, it’s been the mental side of cricket at the highest level that has been the most challenging.

After 15 years of watching Shane Warne bowling teams out for fun in the fourth innings, Australian fans expected the same from the countless spinners who attempted to fill the impossible vacancy left by the King of Spin.

And that’s where Lyon initially struggled, albeit in unique conditions compared to his peers.

"Tall, wiry frame with long, strong fingers" // Getty

"I don’t think it’s an uncommon thing with Australian spinners,” Davison told cricket.com.au on the pressure a spinner feels on the final day of a match when tasked with sealing victory.

"A lot of young blokes talk about their first (Sheffield) Shield game and they get thrown the ball on day four, they’re the only one in the team and everyone is looking to them to win the game for them.

"There is a lot of pressure there. 'Gaz' (Lyon), the first time he probably saw a second-innings wicket might have been in Test cricket.

"There definitely would be pressure on any spinner in that situation, but particularly one who hadn’t played a lot of first-class cricket leading into it."

There has been no better example of Lyon handling that pressure and expectation than in the emotional Adelaide Test match in 2014, where he claimed seven wickets on the final day to spin Australia to victory in a Test he rates as his finest in the Baggy Green.

Hussey says that performance wasn't instant, but rather reward for years of persistence and patience that is now paying full dividends.

The Inner Circle: When Lyon roared In this Optus Sport exclusive, Nathan Lyon reflects on his role in one of the Australian Cricket Team's most famous victories. Posted by cricket.com.au on Wednesday, November 25, 2015

"We have invested a lot of time and effort into him – it hasn't just happened overnight,” Hussey said.

"At certain stages along the way that's been disappointing when we've lost faith in him.

"Ashton Agar came in a played a couple of Test matches ahead of him. (Spin is) a very tough art and in general we've shown a lot of faith and trust in him to do the job, and you've seen him evolve and grow into that role over a period of time.

"There's a really good lesson to be learned out of that; whoever in the future takes over from Nathan, we've got to show the same faith in that guy as well."