That's why the star ruckman has continued to look for ways to improve, despite making his debut over 10 years ago.

Ahead of their round-one clash with Fremantle at Optus Stadium on Sunday, Goldstein is fighting fit - dropping more than five kilograms in the off-season.

"I was really motivated when the season finished to get better," Goldstein said.

"I feel like my best footy is still in front of me and I think that's what's really driven me.

"I've got four or five years at least left, so I want to make sure I don't leave any stone unturned."

The Kangaroos have new additions in former Gold Coast star Aaron Hall, ex-Port players Jasper Pittard and Jared Polec, and former Demon Dom Tyson.

Goldstein said those new players could make the difference, giving the Kangaroos the depth to be consistently competitive.

"I feel like we had the squad last year that was good enough to play finals but we just didn't get that consistency for the whole season," he said.

"We've got high hopes they can make a difference this year.

"If we perform to the level we did in the first half of the year last year I think we've got the cattle to do well and we've got that depth now and that's what you need."

While North dropped both their JLT pre-season games, they travel west with the knowledge of beating the Dockers in their last game there, coming up with a 28-point win in round 10 in what was Goldstein's 200th AFL match.

With the sides fairly evenly matched through the midfield, the ruck battle between the big Roo and Sean Darcy could be key to the outcome.

"I haven't played much against (Sean) Darcy or (Rory) Lobb, who I think will be their two main rucks, so it's going to be tough coming up against the both of them but I'm really looking forward to it," Goldstein said.

Australian Associated Press