Darling earned his first All-Australian jumper last season in a campaign that yielded a career-high 59 goals.

The 27-year-old's contested marking has gone up to an elite level over the past two seasons, and Kennedy believes Darling's growing belief in himself has played a key role.

"He's starting to turn into a bit of a beast of the competition in terms of his marking power and his ability to kick some goals now, which is great to see," Kennedy said.

"He's always had the strength, the speed, the durability to play AFL football.

"Over the years he's really just built that belief. The marks he takes and the goals he kicks - it's just a by-product of that belief.

"Jack's been in a really good space for many years, and I feel like he's just going to keep getting better and better."

Darling is currently sidelined with a fractured cheekbone, but is expected to be fit for the club's season opener against Melbourne on March 22.

Expectations over Kennedy's own output in 2020 are also growing after he was able to avoid post-season surgery for the first time in years.

But the 32-year-old is keen to temper expectations.

"I know there has been a crew who have reported that I said I am flying. I am definitely not flying," Kennedy said.

"And (they) have said that it's the best pre-season I have had. It's definitely not the best pre-season I have had because I am 32 years old.

"I am at that stage where it's just been nice to do all the training - being out there with the boys instead of sitting up in the cardio room looking out the window.

"I am still at the back of every pack when we do running, so I am not as fit as I used to be."

Australian Associated Press