In the days that followed his Test debut, Matt Renshaw received a cryptic instruction from his dad, Ian: go buy some pipe cleaners and a piece of string.

Renshaw had been looking for answers. He had genuinely feared his first Test would be his last. After making an agonising, hour-long 10 in the first innings, he played-and-missed his way through a tortured but ultimately unbeaten 34 from 137 deliveries in the second, as Australia secured a seven-wicket win.

"I felt awful," he remembers. "Chasing that score, I couldn't lay bat on ball."

Some viewed the upside; here was a young batsman who appeared unconcerned by strike-rate, and who possessed the patience to succeed in Test cricket. Others worried about the sketchiness of his technique outside off stump, exposed as it had been by South Africa's probing pacemen.

Ian Renshaw pored through the footage of his son's second innings, and zeroed in on an issue: when the Proteas quicks went around the wicket, Matt had kept his stance open, instead of covering himself by bringing his front foot across as he normally would have done. Whether it was nerves or something else, he had lapsed, and the regular sight of ball beating bat was the result.

Aussie crowd urges watchful Renshaw on

Renshaw didn't actually know what pipe cleaners were, but once that hurdle was accounted for, he did as he had been advised. Then he and Ian went to their local cricket oval at Brendale, in Brisbane's northern suburbs. And just as they have been doing for more than a decade, they played a game.

"I put a pipe cleaner in his back pad on his knee, his hip and his ankle," Ian says. "And then ran the piece of string from off stump to the bowler, which was me with a side arm."

He had borrowed the method from a former coaching colleague, Ashley Ross (father of Redbacks batsman Alex), who had called it the 'string theory'. It was a direct means of addressing this issue of being squared up by the bowler attacking from a different angle. Matt simply had to put his toes on the string and play normally.

"Basically the idea is to keep the pipe cleaners pointed at the wicketkeeper," Ian says. "If you point them at cover, you're squared up."

Matt nodded his understanding, and set about his work. A zany training drill from his father was nothing new. In fact, he has never known any different.

***

Matt was just seven when the Renshaws packed up and moved from Sheffield in England to the north shore of Auckland. Their home in New Zealand sat beside a huge grassy field, where the youngest member of the family swung golf clubs and cricket bats, and kicked a football for days on end. Out front, there was a hill across the road. It was a neighbour's land but it was fair game for Matt, who remembers taking classic catches that his old man would hit to him.

"We'd play cricket and I'd be out there diving around, rolling down the hill," he says. "There were lots of fun games with Dad like that."

What he didn't realise at the time was that Ian was not only immersing his son in sport, but providing him with a platform to be better. A decent cricketer himself, having played alongside Joe Root's father Matt Root at Sheffield Collegiate in England, Renshaw Sr had always been fascinated by the art of coaching, and the impact it could have on a player's performance.

Today, he is an associate professor in skill acquisition at the Queensland University of Technology. He works with sports and exercise scientists and coaches, has written studies on different aspects of cricket coaching and given addresses at coaching conferences.

Renshaw with dad Ian and mum Alison // Getty

In some senses, Matt has been his finest work – though not in a way that has led to a I-hate-my-tennis-dad relationship. In fact, the two are particularly close; Matt describes his father as his role model, and a cool head to speak to when the chaos of professional sport is swirling around him. Ian's knowledge of both cricket and coaching, as well as his intimate understanding of his son, has allowed him to tread the notorious 'tennis dad' line with the caution he is acutely aware he must. It was a process, however.

"He'd probably tell you I had to learn to take a step back," Ian admits. "I knew what he could do in training, and then something would happen in a game, and I'm going, 'How's that happening? In training you wouldn't do that'. But that's the pressure of competition."

So Ian established his own ground rules. He would keep his distance immediately after Matt was dismissed, and he wouldn't try to tell him anything. Instead, when he sensed the time was right, he would gently pose some questions, and allow the steps towards a solution to unfurl.

He also recognised Matt had talent that exceeded his own. Finding ways to nurture it became a sort of education for him as a father and a coach.

"I learnt very early that it's his game," he says. "He sees the world very differently to what I do, which is a very good thing because he's a better player than I was. There's a tendency early on to go (as a coach), 'You can't do that', because of your limitations.

"You have to say, 'Here are the options – this is what could happen', and then let him go and explore. Then he works it out for himself. But it's about that exploration."

Ian would watch Matt play and identify shortcomings in his game, then devise practice sessions around solving those problems. He preferred a centre-wicket scenario to the confines of the nets, because Matt could better see how and where he was hitting the ball. They would set up mini-football goals as fielders for the young batsman to avoid. Sometimes, Ian would have a mixed bag of balls – hard and new, or old and soft – and Matt would work out which gave him better value for his shots. Other days, they would spend the end of a session working on switch and reverse hits; yellow balls would be for the former, red for the latter. In fielding drills, Matt would have to catch balls and then throw at a stump, with the completion of each skill rewarded with a point.

There were scientific theories at play as well. The reverse and switch hitting – and occasional periods spent batting right-handed – were borrowed from the concept of 'bilateral transfer', which states that work on one side of the body leads to improvements on the other. There were times when Ian would encourage Matt to play music during their net sessions, which was designed to relax and free up the body and mind. The intended outcome was an implicit kind of learning, steering away from a direct focus on technique, which could in turn lead to stiffness and the problem of 'paralysis by analysis'.

"I never realised he was trying to build me into what I am today," Renshaw says. "I just saw them as games."

Matt describes Ian as his role model // Getty

Recounted one after another, the sessions could be construed as the product of an overzealous or overbearing parent. But time spent with father and son, and the patent warmth between them, indicates otherwise. Theirs is a bond forged through years of working alongside one another towards an end goal, and within a shared passion. Renshaw insists Ian's knowledge was passed on subconsciously, allowing his skills to develop organically as he went about a pursuit he loved.

"He never tried to push me," he says. "He said, 'If you don't want to play cricket, you don't want to play cricket – that's fine'.

"But growing up I just really enjoyed having fun practising."

He cites another example as a case in point: playing in their driveway, with Ian's arm tiring, a 10-year-old Matt was told that the next time he got out would be bedtime. His solution was to drop the ball at his feet for an hour. As his boy reveled in being allowed to stay up late, Renshaw Sr saw the continued development of a solid defence that would form the sound foundation of his game.

Ultimately, the two of them were in it together, endlessly accumulating tools of their respective trades that would aid them as they advanced their careers.

***

At first, Queensland captain Usman Khawaja didn't quite get the new kid. There was a cheekiness there that could be perceived as arrogance, and a certain cocksureness that didn't chime with a lack of runs on the board. In a Bulls camp that had been moulded under old pros like James Hopes and Phil Jaques, a young, sometimes silly Renshaw ran against the grain.

"I found him tough work just to be around," Khawaja says. "Just his banter and the way he was – there was never any malice or ill intentions, he was just a bit immature."

Renshaw was never the retiring type. He would spin his wheels with some of the other young members of the squad, sometimes acting the smart alec, or trying things in the nets that were viewed as 'taking the piss'. It was all part of his character, and how he had always been – he certainly never intended to cause offence. But none of that mattered to unfamiliar faces.

"People would think I wasn't taking anything seriously," Renshaw says. "Which was tough, because my way of going about my cricket is a bit different to how others go about theirs. Maybe a few people thought I wasn't trying hard enough, or didn't care. That's completely wrong – anyone who knows me, knows I care a lot about cricket.

"But just my persona, people were like, 'He's just being an idiot – he doesn't care, doesn't care about the team'."

Renshaw's relationship with Khawaja has changed over time // Getty

It almost became an issue. But Khawaja had been there himself, albeit in a slightly different sense. At different stages in his development, the 31-year-old has been pigeon-holed as lazy, or lacking the commitment or drive of some of his colleagues. He knows it not to be true, and as such, experience has taught him that perception isn't necessarily reality. And so he was prepared to take Renshaw under his wing.

"He was learning the ropes," Khawaja says. "The more I got to know him, the more I realised I actually did get along with him."

There was another factor, too: age. Renshaw was just 18 when he debuted for Queensland. He was a gifted batsman but he was still a kid in most senses. Professional cricket had arrived quickly but that didn't transform him into an adult overnight. In some situations, he fell short of what was expected in terms of behaviour.

"There were times he could joke around and have fun, and there were times when he couldn't," Khawaja adds. "He needed to find that balance of what was appropriate.

"He realised he needed to grow up a little bit to play with men."

Quite quickly, the tough terrain of professional cricket taught him to curb the cheek. When he was picked in the Test side, he was so conscious of not speaking out of turn around the squad's senior figures that he was dubbed 'the turtle'.

"I didn't want to say anything too strange around Davey (Warner) and Steve (Smith)," he says. "Now I'm learning when to be more myself, and when to be more 'Serious Matt'."

It has been another broad stroke in the Renshaw creation.

***

No player in Australia's Test history has scored as many runs before turning 21 as Renshaw. The swiftness of his rise however, also hastened the inevitable fall. Bradman, Waugh, Ponting et al; the vast majority of this country's batting greats have felt the selectors' axe at an early stage of their Test careers. It was the manner in which they responded that defined them.

"They all get dropped – we know that," says Ian. "And they all have to go away and learn.

"Greg Chappell said (Matt will) look back and that will be the most important six months of his career."

Renshaw was 20 when he scored his maiden Test hundred // Getty

Renshaw regrets the way he approached the beginning of last summer's Sheffield Shield season. He knows he got caught up in the 'Ashes selection trials' talk that was played up in the press. Then there were the media commitments in the lead-up: interviews and photo shoots that were a long way removed from the successful routine he had forged. At home, he knew he had family who had booked flights from the UK and bought tickets for the first Test at the Gabba. His mum worried constantly on his behalf about selection. They were all distractions spinning around in his head, and each failure in the middle had a snowball effect on his psyche.

"I was struggling quite a lot, there's no question about that," he says. "I know it sounds bad, but I was trying too hard to get picked for those Ashes Tests."

The silver lining to missing the Ashes came in the form of time and space. To breathe, and to reevaluate. The Shield season took its break for the Big Bash and as a Brisbane Heat squad member, Renshaw had time to observe stars Brendon McCullum and Chris Lynn in the nets, as well as in the burning spotlight of Twenty20 action. They employed different training methods to him as they prepared for another kind of batting challenge. They would refuse to let bowlers settle into any kind of rhythm, seizing the initiative with aggressive shot-making. His mind ticked away, the lateral thought processes instilled in him from childhood finding potential solutions to his form concerns via a parallel cricket universe.

"Watching some of those guys, the key thing he noticed was that they were standing still for as long as they could," says Ian. "That's hard (when you're facing) 150kph, but looking at him now he seems to be doing it much longer."

BBL helped shift Renshaw's mindset // Getty

Renshaw began paying more attention to his fitness. Coming through the ranks, he had struggled at times to hit the required skin fold targets. And prior to the Big Bash break, his preoccupation with trying to cement an Ashes spot had come at the expense of just about everything else. His weight climbed to 98kg.

So in the heat of the Brisbane summer, he changed tack. In the hours before BBL matches, he was running laps of the Gabba, and sweating his way through sprint sessions in the outfield. It was before the crowds had rolled in, under the still-sweltering late afternoon sun. The recalibration proved beneficial mentally as much as physically.

"I had been thinking too much about the runs," he says. "As soon as I concentrated on my fitness, I had another outlet to go to."

In January, he ran a personal best in a 2km time trial, dropping 20 seconds from his pre-Christmas result of 8:03. His fitness improved to the point that he shone in three Twenty20 club games for Toombul across a day-and-a-half. He had seen it as his best means of convincing selectors he was worthy of a start for the Heat.

"I went 80 and 100 on the Saturday, and 70 on the Sunday," he says. "I don't think I would've been able to do that if I hadn't been as fit as I was."

Brisbane's campaign unraveled but Renshaw earned a debut in their final match of the season, making 22 batting at No.4. He had lost five kilos from his 185cm frame (weight he has kept off) and began incorporating a fitness focus and a more intelligent approach to his diet into his daily routine. The exposure to a different format and the fresh challenges that came with it rejuvenated him. He went back to training with Queensland with new ideas about how to advance his game.

***

The Big Bash experience promoted within Renshaw a more attacking mindset. It was an outlook that was endorsed by Bulls coaching staff, in particular Hopes, who saw untapped potential in him as more of an aggressor at the top of the order. The tall left-hander reminded him of Matthew Hayden, whom Hopes had played alongside with Queensland. The Renshaws had heard the comparison plenty of times without giving it more than a passing thought, but there was substance to it.

"I didn't see a lot of Hayden (play), outside of the Ashes," says Ian. "Everybody had always said (to Matt), 'You're left-handed, you're from Queensland', and we thought it was just that and the name.

"But then Hopes showed him the footage."

The Bulls assistant coach had set up a split screen of the two men batting. Shown in such a direct way, the comparison really struck Renshaw. It was encouraging; here was a natural likeness to one of the most prolific opening batsmen in Test history. But it also raised more questions. If their techniques were so similar, why did he lack the shot range of Hayden on the off side? He looked at the vision more closely, over and over. Soon enough, the answer presented itself.

Renshaw's change to mimic Matt the Bat

"Watching that footage, being able to see it side by side, I noticed he had a lot better posture," Renshaw says.

"So I went into the nets and tried to stand up straighter.

"It seemed to work. The falling over didn't happen as much, and I found this off-side game that I'd never had before."

Renshaw and Hayden had spoken in India almost a year earlier, after the second Test in Bangalore. The 103-Test veteran had seen the young batsman regularly advancing at spinner Ravindra Jadeja without appearing to have a considered plan – a strategy that ended with a leg-side stumping. Hayden offered him a new perspective.

"He compared it to a boxing match," Renshaw says. "You need to throw some punches. Back away and defend for a bit. Go out, throw another punch.

"I really liked that analogy. It's made me think of it like that."

Renshaw immediately felt in sync with Hayden. He valued the way he spoke to him. In the space of five minutes it was as if the curtain had been tugged open just a little to reveal a few secrets of batting at the highest level.

They crossed paths again at the Gabba, ahead of the first Shield match of the new year. Hayden had been invited in by Queensland coach Wade Seccombe, and shared some thoughts with the batting group on the art of spending long periods in the middle, and on winning first-class cricket's war of attrition. The psychological insights were valuable for Renshaw, who was also in the process of making some technical adjustments; slight shifts in the position of his feet and his head, and a more Hayden-like posture. When Queensland faced Victoria at the MCG in February, he felt ready to bundle it all together.

"I didn't want to put any pressure on it," he says of the changes. "If it happened, it happened."

He took that relaxed approach to the middle. Instead of overthinking the new technique, he focused on particular songs in his head, replaying them over and over. Childish Gambino. Sam Smith. Rudimental. It was the soundtrack to his reinvention. Renshaw smashed 170 from just 218 deliveries against the Vics, and followed up with centuries in his next two Shield matches. In the competition decider, he controlled the final-day run chase, cruising to an unbeaten 81 from 83 balls as Queensland won the title. The contrast between that performance and his painful 37no on Test debut underlined the extent of his development.

Renshaw dominates with superb hundred

The purple patch was timely; the ball-tampering crisis in South Africa meant there were batting places up for grabs in Australia's Test team. Hours after hitting the winning runs in the Shield final, Renshaw jumped on a flight to Johannesburg. He slept the entire first leg to Dubai. When he woke up, he had forgotten it was his 22nd birthday.

***

By early June, Renshaw had scored more first-class runs for the calendar year than anyone on the planet. His six hundreds had come at a rate of one every two matches, and his 1,139 runs were scored at a strike-rate of 66.14 (compared to a career mark of 49.34).

In unique circumstances at The Wanderers, he failed twice in his comeback to Test cricket. But in a wider context, he had taken the first difficult steps in the next phase of a journey towards the fulfilment of his potential.

"It was massive getting that recall," he says. "I was trying not to think about it too much, but obviously you want to play as much as you can for Australia."

It was Renshaw's 11th Test, and the signs are encouraging he will add considerably to that number. Khawaja has seen a maturing in him across the past three years, and a work ethic many had doubted he possessed come to the fore.

"He's still very much 'Renners', but he's grown up a lot," he says. "I like to think we're not even close to seeing the best of him."

Renshaw scored hundreds in his first two county matches // Getty

Certainly Justin Langer will be hoping that is the case. Australia's new coach was at the Gabba when Renshaw piled on 143no in quick time against Western Australia in March. He was taken by the likeness to his former opening partner, a man he had watched more often – and from closer quarters – than anyone.

"Honestly, it was like watching Matthew Hayden bat," Langer remembers. "He creamed them.

"At that stage I was spewing because he was playing for Queensland, but now as the Australian coach, I'm glad I saw that innings."

Langer has a long association with Somerset, where Renshaw was so impressive this northern winter before a broken finger ended his time in the UK. When he was appointed national coach, he texted Renshaw, telling him to stay fit and to continue making runs. He will doubtless have had his spies keeping an eye on his potential superstar opener, ensuring he was checking the boxes he needed to as a young professional cricketer learning the game.

But Renshaw's favourite mode of education is still happening much closer to home. Last summer he bought his first house, located just a five-minute drive from his parents' place and 15 minutes from Queensland's training base in Brisbane. It kept a couple of the most important things in his life at arm's reach. In the days leading up to the Shield final, he texted his dad. They met up at their park, and as Ian littered the outfield with pool noodles, Matt cranked up some music. The first song he played was Rudimental's Not Giving In.

Together, they stood in the middle of the vast, green expanse, and played a game.