SELF-BELIEF is as potent as performance-enhancing drugs on an athlete's output, a university study once suggested.

The British study found that a lack of assuredness can have debilitating effects and override ability and competence, but a positive dose has the potential to lift sportspeople to great heights.

Hawthorn's unflappable rebounding defender Ryan Burton can attest to both.

Burton has set about proving people wrong ever since doctors told him he would never play the game again after a horrific leg break in 2014.

That takes a form of confidence in itself, something many will tell you the 2015 No.19 NAB AFL Draft pick always possessed. But doubt still plagued him, even after the Hawks drafted him and he played four senior games last year.

A forward for most of his junior career, Burton was swung into defence early in his AFL career and performed well enough to play in a final.

Still, the 20-year-old wasn't completely comfortable, particularly in the defensive 50. A player always among his junior sides' first picked was suddenly overcome with anxiety at selection time.

Burton, the Hawks' first top-20 pick since triple premiership star Isaac Smith in 2010, was right to be concerned, too, because he was left out of the club's round one side this year.

Fast-forward nine weeks and he has a NAB AFL Rising Star nomination under his belt, is considered a leading contender to win the whole thing and is certain to be chosen each week.

"It's a bit easier when you're playing some OK footy – you don't have to worry about things like that," Burton told AFL.com.au this week.

"I was worrying about that a fair bit at the start of the year in the JLT (Community Series) and I saw my form drop, because I was worrying about it so much.

"So at the moment I'm just taking it week by week and focusing on what I have to do in the game and it's definitely helping."

Luke Hodge and Josh Gibson still point him in the right direction down back on occasion, but Burton is fitting in wonderfully as Hawthorn's Mr Composure.

The 191cm swingman's emergence, including averages of almost 21 possessions, six marks, 353m gained and four rebound 50s, has been a huge bonus with the Hawks missing Grant Birchall for all bar three games. 

Of the 125 players to have at least 100 kicks this season, Burton's kicking efficiency of 84.9 per cent ranks No.1 in the AFL.

That status is rammed home further when you consider his disposal efficiency of 87.2 per cent in the defensive 50 is top 10 among the 97 players with at least 50 possessions in that area.

"I guess it is natural. I haven't really worked on it too much," Burton said.

"I work on my decision-making a fair bit, which probably comes into it, but I just try and take the best option every time I get the ball and try not to make a mistake.

"I didn't think I'd get to where I am at this early in my career, especially after the surgery (to remove the plate in his leg) last year, but I'm definitely pleased with where I'm at."

Ryan Burton has been outstanding in defence for the Hawks. Picture: AFL Photos

Hawthorn's backline coach, Cameron Bruce, analyses Burton closer than anyone and likes what he sees – both in what he offers now and what he could become.

Bruce raves about the North Adelaide product's versatility and is in no doubt he is good enough to develop into a tall midfielder.

"His confidence in his ability is … it's not an ugly arrogance, it's a real confidence the real good players do have," Bruce said of Burton.

"He is willing and hungry to improve and wants to be the best player possible.

"Those signs in terms of self-confidence and then in big games to have that composure in pressure situations, and particularly deep in defence, are setting him up to be a really good player."

The number of past greats lining up to hail Burton increases by the week and the Hawks' all-time leading goalkicker Jason Dunstall was the latest on Monday night.

Dunstall presented Burton with his guernsey on debut last year.

"I have a lot of time for this bloke," Dunstall said on Fox Footy.

"He can play at both ends of the ground and they've let him settle in a key defensive post, and I think he's developed brilliantly."

Burton's composure extends off the ground, too, with his elevation to former captain Sam Mitchell's No.5 in the off-season failing to intimidate him.

He stopped short of making a Christian Petracca-like statement about wanting to be a Hall of Famer, but his explanation on why the number hasn't burdened him sums his outlook up.

"People asked if I felt the pressure when they gave me No.5 and I said 'No'," Burton said, surrounded by chronicled moments in the Hawthorn Football Club Museum at Waverley Park.

"It's obviously a very prestigious number, but I am trying to forge my own history."