CLAYTON Oliver's career is going swimmingly.

Still just 20, Oliver is Melbourne's reigning best and fairest winner and producing numbers rarely seen in such a young player in only his third season in the League.

The star midfielder has won 30 or more disposals on 15 occasions – the most recorded by Champion Data since 1999 for a player in his first 42 games.

Oliver has gathered 20 contested possessions in a match six times – one more than Patrick Cripps (five) and ahead of Nat Fyfe and Chris Judd (twice) – in that same 42-game period.

Since entering the AFL as pick four in the 2015 NAB AFL Draft, Oliver is ranked seventh in the competition for loose-ball gets, eighth for handballs, ninth for effective handball and 10th for ground-ball gets from 2016-18.

And, like a swimmer working on perfecting their stroke, Oliver is always searching for ways to get better.

BE FIRST IN THE KNOW Get Breaking News alerts with the AFL on Messenger

Being able to run out games more effectively was a focus area for Oliver in his end-of-year review and that's why an aim of swimming 100km over the pre-season has him in the best physical shape of his career.

Five or six times a week over the summer months, as an extra session, Oliver and teammate Sam Weideman swam laps in the pool with the primary focus of improving their fitness so they would be better conditioned for the 2018 season.

"I'm not the fittest player at the club and neither is 'Weido' (Weideman), so we thought we'd try to do 100km of swimming for the pre-season and (co-captain) Nathan Jones got in there for a little bit and he did about 30km," Oliver told

"I'm way fitter than what I was last year and my 'skinnies' (skinfolds) are a little bit lower than what they were and I just feel better overall."

Oliver has averaged 28.1 disposals, seven clearances (sixth in the AFL) and almost seven-and-a-half tackles (equal third in the AFL) a game so far this season. He is coming off an equal-career high 36 touches (including 28 handballs) against St Kilda last week.

WATCH: Oliver slams one home against the Saints

Underlining the stellar form he has produced to start the year, you need only keep in mind that he is ranked No. 1 at the club for clearances, contested possessions, ground-ball gets, handballs, hard-ball gets, loose-ball gets and pressure acts.

Oliver's also second at Melbourne for centre bounce clearances, effective disposals, score launches and tackles.

There was plenty of discussion about the amount of handballs Oliver fired off against the Saints, with the gun on-baller having just eight kicks for the afternoon among his 28 handballs.

But Oliver isn't going to change his game for the sake of it.

"If I kick it, I kick it. If I handball it, I handball it. It just happens more often than not that I need to handball it and if someone's in a better position than me, then I'll give them the ball," he said.

Oliver has vastly improved his professionalism in the past two seasons, developing the habits required to be an AFL player in the past 18 months.

He said doing the 'extras' comes naturally now and he was even trying to pass on those traits to guys such as Charlie Spargo and Bayley Fritsch in their first seasons in the League.

"I enjoy doing it. It's about getting through each day and doing everything that I need to do. You've got your best mates at the club and doing it with them makes it really enjoyable," Oliver said.