It seems contradictory for a guy unbeaten in the UFC and riding a 19-fight win streak ahead of the second defence of his featherweight title on Sunday.

He's absolutely certain he won't lose, with the confidence born of doing just that in the gym.

In preparation for his bout with Brazilian jiujitsu black belt Brian Ortega, the Wollongong native spent day after day rolling on the mats with Craig Jones.

His fellow Aussie is one of the world's finest grapplers, a jiujitsu black belt with a seemingly endless list of accolades to his name across multiple weight classes, and as high 205 pounds.

Even the best 145-pounder in the UFC, possibly ever, is outclassed against Jones on the mat. However, through filming of The Ultimate Fighter series, Volkanovski spent just about every day trying to beat Jones at his own game.

Far from an exercise in futility, those sessions are the reason Volkanovski doesn't fear the grappling of Ortega this weekend, despite many thinking the mat is the Californian's world.

"I do endless rounds with Craig Jones knowing I don't have a chance," Volkanovski said.

"He's bigger than me, he's one of the best grapplers in the world, but I put myself in those positions. That's the type of guy I am.

"I'd rather lose in the gym, I'm willing to experience all these things. I am perfectly fine being uncomfortable.

"People sit there and say [Ortega's] a whole different challenge for me, and maybe as far as UFC fights go he is, but they're not challenges I've never seen before.

"I guarantee you, all the positions he thinks he's going to put me in, I've been there a million times and with people better than him.

"He's going to learn real quick, no matter where we go, he ain't going to be comfortable and he ain't going to have me in trouble.

"He's going to be fighting my fight and he's going to crumble."

It's part of the mentality that has him reigning over the division, with his list of vanquished opponents its own Hall of Fame.

From the crazy volume of Max Holloway, to the precision striking of Jose Aldo, the explosive wrestling of Chad Mendes, Volkanovski has handled it all because he's the one who can do it all.

He's far from done in that regard. While a third fight with Holloway - the man he deposed - is inevitable down the track, he retains a thirst to fully clean-out the division.

"I haven't yet," he said.

"We've got a bunch of killers, a lot of up and comers. It's a stacked division, so to be a champ in the featherweight division is pretty incredible. You take out No. 1 contenders like Ortega and, with the guys on my resume already, you start to really say something.

"I don't think I'll have wiped out the division, but I've already taken out the GOATs of the division (Holloway and Aldo).

''I am well on the way to reaching that GOAT status."

With those wins over Holloway and Aldo, he makes a compelling argument, certainly in the lineal man-who-beat-the-man sense. He's not done either.

This week Ortega said he'd consider winning the title "mission accomplished." For Volkanovski, that achievement was merely the beginning.

"There's always more to do. Being the champion isn't enough," Volkanovski said.

"Reaching the championship belt is a goal, but it doesn't end here. You can't just sit there and say 'I want to be champ one day' and once you're champ think 'how good's this' and get complacent.

"Fighting for the belt wasn't enough, winning the belt wasn't enough, defending wasn't enough. I want to defend again, you want double-champ status, you want GOAT status. The goals are going to be endless and we keep moving."

Of all their differing attributes, that's the main difference the 32-year-old out of Windang sees between himself and his opponent.

Ortega has unquestionable title claims, despite falling short in his first chance against Holloway in December 2018.

If his previous victory over 'Korean Zombie' Chan Sung Jung is any indication, he's a new-and-improved version of that fighter.

Yet, with the TUF experience providing far more time at close quarters than an ordinary fight build-up, Volkanovski sees a guy bereft of the qualities that define a champion; spitting particular venom around Ortega's past doping violation (in 2014) on Friday.

"He hasn't been the champion, he should have crazy drive to get this done but he doesn't want it," Volkanovski said.

"Even listening to his interviews, things he's saying, he's already building in excuses.

"He's talking about what he's doing next, he's already talking about moving up [in weight].

"When I beat him, he's going to say 'all good, I was going to move up anyway'. He's already talking like that, committing to other things.

"He ain't ready to be the champion. He doesn't deserve it. You can see it, he doesn't want it like I do."