Australia's Will Tomlinson expects his defence of his International Boxing Organisation (IBO) world title to earn him a unification fight overseas.

Australia's Will Tomlinson is eyeing a unification bout in the United States after successfully defending his International Boxing Organisation (IBO) world title.

Tomlinson expects his unanimous points win over Klassen - a former two-time International Boxing Federation (IBF) champion - to lift him into the top five with each of those bodies.

"So a unification of my IBO world title with one of the other belts surely has to happen," Tomlinson said.

"I've been working towards this for quite a few years now and this is the path that we've had to take.

"It's been a slow process but boxing is a slow process, especially when you're up at that top level.

"But I'm super stoked with my performance and getting a win over such a credible fighter."

Tomlinson, now unbeaten in 22 fights, is yet to fight outside Australia, but is confident his dream of heading to the United States is about to be realised.

He rated Thursday night's third successful defence of his IBO title the toughest fight of his career so far.

The Australian was very much the aggressor, as his fleet-footed 31-year-old opponent ducked and weaved around the ring, making Tomlinson chase him then trying to counterpunch.

At one point in the fourth round, Klassen, with his back on the ropes, ducked under a Tomlinson punch, ran to the other side of the ring, poked his tongue out and smiled at the Australian.

"That's exactly what I was expecting, a very arrogant fight on his behalf," Tomlinson said.

"I had a good feeling that he wouldn't have been able to out-strength me, as a lot of my other opponents can't.

"I believe I'm a pretty strong super featherweight.

"But I knew he was going to be slick and fight a slick fight and he definitely did.

"But obviously when you're fighting a champion in his home country, you've got to take the champion's title and there's no way he did enough to get close to that."