JACK Steven might come across as laidback and carefree, but on the inside lurks a fierce competitor determined to excel at everything he does.

The St Kilda midfielder is reserved by nature, lives quietly in East Brighton with his girlfriend of five years, Indi, and their six egg-laying chickens, and heads home to Lorne whenever he can.

He does not do much media and shuns the limelight, as evidenced by his determination to have his out-of-contract status resolved before the start of this season.

But the 25-year-old's killer competitive instinct is what turned a local footballer who played in two senior premierships before he was 17 into one of the League's prime midfielders.

On the eve of his 100^th game Steven has shared some insights into what helped him become a best and fairest winner at the age of 23, and why – along with teammate David Armitage – he has become one of the more dangerous ball-winners in the competition.

"I've always wanted to be the best at what I do," Steven told AFL.com.au this week.

"I just get addicted to things really easily and I have to keep doing it until I've nailed it.

"That's how I do everything. I'm just extra competitive."

After spending most of his childhood surfing and playing golf in his Victorian surf coast hometown, Steven dabbled in cricket and football but didn't take either seriously.

He progressed from under 14s to Lorne's senior team by the time he was 16, and played in back-to-back premiership teams in 2006 and 2007.

After putting a "disappointing" state team performance behind him in 2006, it started to happen the following year with the Geelong Falcons.

He had a "solid season" but was told not to expect to be drafted.

But he was, and at the age of 17 and with a year of school to go, Steven left home and headed to the big smoke to live with a host family.

He enrolled in St Bede's in Mentone, where he would spend weekday mornings studying for the three subjects he needed to finish year 12, and the afternoons at the Saints. 

"It was probably the biggest year of my life," he said.

"I'd gone from a pretty cruisy sort of school in Lorne to living in Melbourne and I was in an AFL environment.

"I was No.34 so I was next to Robert Harvey and he'd played for two years before I was even born.

"It was all pretty surreal."

His AFL career started slowly, which isn't surprising given how many things Steven had going on in 2008.

He didn't play seniors in his first year, and then in 2009 the Saints didn't lose a game until Essendon defeated them in round 20.

But the week before, in a smattering of strategic omissions for a Launceston encounter against Hawthorn, Steven was handed his first game.

"It was why I got a game," Steven reflected about former coach Ross Lyon's selection policy for the late-season game.

"But I just realised how much better it was to play seniors and when I got that taste, I knew where I wanted to be and it made me more focused to stay in the team."

After a hiccup last year when a pre-season foot injury took a chunk out of his summer training and affected his fitness all season, Steven is back on track.

His loads were carefully managed this year, demonstrated in his blistering form that has been somewhat overshadowed by Armitage's startling season.

But his effort has not been lost on coach Alan Richardson, who says he has stepped up not only as a player but also a leader.

"He's one of those players that inspires and almost embarrasses people into greater effort because of his energy and enthusiasm and passion for the game," Richardson said.

"He loves the game, he loves playing with his teammates, he gives real spirit and energy to the way his teammates play because of his own actions.

"There's been a lot of talk for all the right reasons about Dave but Jack is ranked third in the competition in respect to putting pressure on the opposition.

"Some of the work he's done on the inside has been as significant."

Steven could have been one of the hottest free agents on the market this year if he had wanted to be.

But he did not consider leaving the club he has grown to love and inked a five-year extension before the season began. 

"I didn't go in and demand five years or anything. That's where the negotiations got to and everyone was happy," Steven said.

"[Free agency] is a good thing if you want to move but I was really happy.

"I was really lucky the Saints were happy to have me … and I was happy to stay."

So while Steven continues to go about his peaceful life with Indi and chickens Betty, Summer, Audrey, Pearl, Silver and Thelma, and starts to contemplate what he wants to be when he is no longer a footballer, he will always have that must-win streak bubbling under the surface.

He will use it to make sure he gets everything he can out of the next 100 games.

"I haven't nailed footy yet – I don't think you can," he said.

"It's a trait that keeps me in good stead at footy because obviously you've got to be pretty intense about how you go about it with getting the ball and attacking your opponent.

"It just helps with my effort, and it's just how I play – with everything I've got."