FREMANTLE midfielder Caleb Serong is on the verge of setting a new VFL/AFL possession record, and he credits his work with a sports psychologist for his consistently hot form.

Serong won his third Glendinning-Allan Medal in last week's 35-point Western Derby win, with the 23-year-old tallying 32 disposals, 10 clearances, 525m gained and a goal.

It marked the 70th consecutive game Serong had racked up at least 20 disposals, equalling the record held by Western Bulldogs midfielder Jack Macrae.

He will have a chance to break the record when he lines up against Essendon at the MCG on Sunday in what also marks his 100-game milestone.

The 180cm midfielder is rated fifth favourite for this year's Brownlow Medal, and last season he won his maiden All-Australian blazer as well as Fremantle's best-and-fairest award.

Serong says his stunning performance against West Coast was not a case of him lifting for a Derby, but rather him maintaining a consistently high standard.

"That's something I've worked heavily on with my mental skills and worked with sports psychologists," he told reporters on Monday.

"A big focus is when we do get to Grand Final day ­­– whenever that is – I don't feel like I ... have to lift to that occasion.

"Every time I train, every time I play, I want to be doing it at that level and intensity, so I'm ready to go when that time comes."

Serong started his regular work with a psychologist in the lead-up to last season, and it's worked wonders for him.

"A lot of guys across the League are investing more time in that as they go along, and I'm no different," he said.

"I've found a great improvement in my own game in that space.

"You can have the physical side of your game down pat, and then the mental side, if that's not at the same level ... it can affect the way you play no doubt."

Serong's remarkable run of games with 20 or more disposals hasn't come easy, with rival teams regularly sending taggers or 'coolers' to him.

"Some weeks you walk out there and you're getting someone run with you the whole time, and you feel like you can't get near it or have an impact on the game," Serong said.

"Those challenges and understanding how to manipulate that and be a better player for the team ... has been a big growth piece for me this year. 

"The support I've had from my teammates and the other midfielders ­– it's a great midfield to be a part of."

Fremantle takes on Essendon (MCG), Geelong (home), Greater Western Sydney (Giants Stadium) and Port Adelaide (home) in a tricky run that will decide its top-four fate.