MELBOURNE duo Clayton Oliver and Angus Brayshaw remain locked in a sugar-free battle as they attempt to shave off pre-season skinfolds.

Pivotal to the Demons' rise in 2018 with career-best seasons, the star midfielders have entered into a competition over who can last the longest without giving in to temptation.  

While Oliver entered the AFL with a diet described as "atrocious," the Virgin Australia AFL All Australian's new regime has provided instant success.

"Me and 'Gussy' Brayshaw, our diets are usually pretty good, but we decided to cut out sugar for the pre-season," Oliver told AFL.com.au.

"We've got a little bit of a bet on to see who can hold out the longest for not eating chocolate, soft drink or any sugar.

"(It's been) since day one because we've wanted to get our 'skinnies' down, which is pretty important and keep your muscle-to-weight ratio higher. Hopefully the lower skinnies, the better.

"They've (skinfolds) been the best they've been so it's obviously worked a fair bit. (I'm) running real well and so is Gussy, Gussy's flying."

Asked for a please explain after devouring chicken parmigianas in his first year at the Demons, Oliver's latest experiment comes as part of a professional approach that has elevated him to one of the League's leading ball-magnets.

Last pre-season he notched 100km in the pool, identifying the need to increase his aerobic capacity.

And now after sharpening his diet, Oliver will finally be able to relax on Sunday night when he returns home to Shepparton for the Demons' pre-season opener against Richmond.

"It's been pretty tough, the first three or four weeks were pretty average. After that you get over it and it hasn't been too bad," Oliver said.

"We'll stop for the first JLT (Community Series) game so Gussy can have his post-game snacks."

Co-captain Jack Viney is another Demon tinkering with his diet, opting for a daily 16-hour fasting method where he only consumes food from 12-8pm.

While Viney will be missing on Sunday, Oliver's inclusion comes after a speedy recovery from surgeries on both shoulders in October. 

"I got a Latarjet surgery on my right shoulder and then got an arthroscope on my left. I've been in rehab for about 16-20 weeks but it's coming good now," Oliver said.

"It's all been pretty smooth sailing, just with the pain (I've) been trying to manage that, once that's completely gone I'll be right to go."

While Oliver averaged 29.4 disposals a game last season, he has flagged potentially more time in attack this season as the Demons rotate their midfield depth.

"I think there's going to be me, Vines (Viney), Trac (Christian Petracca), Gus, James Harmes, all of us midfielders with the ability to go forward and try and impact the scoreboard," Oliver said.

"When we need a rest, instead of going to the bench we can go forward for three or four minutes and have two or three of us sliding through there. It gives you opportunities to stay in the game.

"(I've spent a) fair bit of time on my goalkicking, my marking's always been a bit of a strength, probably not the one-on-one stuff, but flying for the ball."

After being taken with pick No.4 in the 2015 NAB AFL Draft after claiming the TAC Cup's Morrish Medal, Oliver was on hand for the competition's re-brand to the NAB League last week.