JOSEPH PARKER has lifted the lid on a sparring session he had with Andy Ruiz years ago as the two unbeaten heavyweights prepare to contest the vacant WBO world title this weekend.

The New Zealander has home advantage at the Vector Arena in Auckland and is the betting favourite to be crowned champion.

However he admits Ruiz got the better of him when they sparred in the past, though claims he was just a novice at the time and that things will be different when they trade leather in earnest.

“Yes, we did spar together.  I was in Las Vegas and new to the sport,” he said. “I went in to spar with him [Ruiz] and thought it would be easy because of his size but when we were sparring he hit me pretty good and he chased me out of the ring and now I have to get him back for that.  He’s coming to my backyard.  I have to defend my country’s honor.”

Parker, having fought almost exclusively in New Lealand, is a star among his people and recently teamed up with promoter Bob Arum – who also promotes Ruiz – in a bid to raise his profile in America and China.

“We use the same routine for this fight as all the others – it is the one that has always worked,” he said.

“I will use the support in the building to motivate me and that will drive me throughout the fight. Andy wants to take the belt back with him and I want to keep it here.  I want to go out there and win this and win it well.

“I know Andy is a nice guy and there is no hate between us.  But when the bell rings on Saturday night we flip the switch and we will each be trying to knock the other guy out.”

Ruiz, usually quite portly, has trimmed down for this fight and insists he is in the shape of his life. His 29-0 (19) record looks good on paper though it lacks a standout win – the Californian plans on changing that this weekend.

“This is my chance and I didn’t come all the way to New Zealand to lose,” he said.

“I know everyone is underestimating me.  I know I trained hard for this fight.  I hear everyone commenting on how I look physically, but imagine now that I am in great shape, how good I will be on Saturday night.  I know I am an exciting fighter – I will use lots of footwork and throw a lot of combinations – and we both hit hard.

“This is a great opportunity for me and I’m not leaving New Zealand without that belt.”