His NSW teammates are usually sheltered from the repercussions of that, but a rare time they were not was in a City versus Country intra-squad match in the pre-season.

Having heard whispers about the way he bowled in that match, I put it to him that he struck one of his teammates in the helmet. While remaining extremely polite, he corrected me: it was two he had hit, not one. Peter Nevill was relatively unscathed, but precocious teen Jake Doran suffered migraines afterward.

"I'm definitely pretty quiet off the field, but I like to get stuck into them [batsmen] while I'm out there," Hazlewood said with a wry smile.

In both instances the batsmen were, in Hazlewood's opinion, too settled playing off the front foot. Delivering a shock, well-directed bouncer affects not only the batsmen facing but the rest of his teammates, because they see what could be coming to them.

Hazlewood was the first of the new breed of fast bowlers to get a taste of international cricket. When he played a one-dayer in England in 2010 he was, at 19, Australia's youngest-ever one-day representative. He was eventually overtaken for that title by Pat Cummins, one of many things he was overtaken at.

Having grown to close to his current height of 196 centimetres by his mid teens, Hazlewood was identified very early by the NSW hierarchy as a rare talent.

He does not turn 24 until January but he is, remarkably, in his seventh year of holding a playing contract, with the Blues so keen on him they allowed him to spend his first year on their list at home in Tamworth while he completed year 12. Almost immediately after his final exams he was, at 16, opening the bowling for the Blues in late 2008 on the SCG in a tour match against New Zealand, in which he claimed four wickets across the two innings.

After making his one-day debut for Australia within two years of that game, he was chosen for a Test tour of India, but had to withdraw after suffering - as is typical for a young quick - stress fractures in his back. Since then, seven fast bowlers have debuted: Peter George, James Pattinson, Mitch Starc, Trent Copeland, Pat Cummins, John Hastings and Jackson Bird. Hastings' chance, two years ago in Perth against South Africa, came after Hazlewood developed foot soreness in the nets, which was later revealed to be a serious injury.

While Hazlewood is happy for his peers - Starc has been a long-term teammate since under-age competitions, Pattinson a long-term opponent - that has not stopped him from feeling envious at their progression to Tests ahead of him.

"It was quite hard seeing those guys play . . . and go past you," he said. "But I feel that I'm more experienced now. I've been back playing a few years of shield cricket and one-day cricket and I'd feel more comfortable at the next level than if I'd probably had a crack then. It might be better in the long term."

The injuries that have afflicted Hazlewood have primary been bone-related. He is confident that was a near-inevitable repercussion of being a young fast bowler and that he is "past the worst".

"You're always going to have niggles . . . but hopefully I'm past those long-term injuries, with my bones healing and I'm getting stronger," he said.

Of the "big four" emerging pacemen - Hazlewood, Cummins, Pattinson, Starc - Hazlewood is the least conspicuous. Cummins has dazzled with his express pace, Pattinson for his fast outswing, Starc for his inswinging yorkers and steepling bounce. Hazlewood's strength is his dependability.

Some fast bowlers may consider it a slight to be considered a "stock bowler", a role that has made Peter Siddle a mainstay of the pace attack in recent years. Hazlewood, however, takes pride in being able to fulfil that role. But to do it successfully, Hazlewood reckons maintaining a consistently high pace, and the ability to slip in a lethal bouncer, is essential.

"Everyone has their strengths and weaknesses. It's just a matter of getting those right combinations . . . getting two or three quicks that are a little bit different," he said. "On the wickets that they play on - even in Australia where the Test wickets are a lot flatter than the shield wickets - you need to have to get that extra bounce and extra movement at that 140 mark to threaten than batters at that level. If you're going to roll in and bowl 130 it's pretty easy work for the batters.

"I think you have to have that [change-up in pace] as a quick. You can't just keep throwing the ball up and them driving it back past you and getting their confidence up. You need to have that up your sleeve . . . all the quality quicks have that."

Hazlewood never takes appearances for Australia in any format lightly, but he is rapt to not be part of the looming Twenty20 series against South Africa, because it will give him - and fellow Test pace candidate Nathan Coulter-Nile - a chance to play two Sheffield Shield games ahead of selection for the home Tests against India. Selection against India, at some stage of the series, could be the start of the metronomic Hazlewood reclaiming some of the ground he lost to his peers in the past four years as his body failed him.

"I think everything is sort of rolling my way at the moment," he said. "My fitness is good and the ball is coming out nicely, and a few of the other guys are injured so that leaves the door open for new guys and a few opportunities. It's heading that way, but it's up to me to keep it heading that way."