Good but not good enough – that's trainer Kevin Barry's verdict on the latest boxer to line out against his prized heavyweight Joseph Parker.

Australian Bowie Tupou enters the ring with Kiwi Parker in Invercargill next weekend in a clash that has big ramifications for the WBO rankings.

Tupou, tipped to be around 120kg for the fight, brings power to go with his size.

But Barry knows Parker has the goods to handle.

"This is a massive opportunity for Bowie Tupou and I think we will get the best Bowie Tupou that there is," Barry said of an opponent boasting a 25-3 record that includes 17 knockout victories.

"I personally think that the best Bowie Tupou doesn't beat the best Joseph Parker.

"But it's a fight that we have prepared very well for; and it's a fight where we must get things right.

"It's fight that could be a very easy fight for Joe if he gets everything right. It's a fight that if he gets caught with an overhand right could make it a very difficult fight.

"I need Joe to be smart, patient, disciplined and to control things form the outside and not let Tupou into the middle zone where he can be dangerous.

Barry's main concern is Parker's vulnerability to the overhand right, a defensive weakness that has been exposed several times during his unbeaten 14-fight professional career. It's something they have worked hard on during their latest training camp in Las Vegas.

"I have a lot of respect for his power, he has real heavyweight power," warned Barry who said Tupou's classy handlers would ensure he entered the ring in good shape, physically and mentally.

"I have respect for Jeff Fenech. He will motivate Tupou to the hilt and will bring out the best in him.

"Believe me, this is a real fight for us."