World heavyweight champion Wladimir Klitschko has had numerous close encounters with Joseph Parker's next opponent and the Ukrainian veteran believes Parker will be in for a tough night in Germany in two weeks' time.
Parker will meet the experienced Sherman Williams on the undercard of Klitschko's world title fight against Alex Leapai in Oberhausen on April 27 (NZT).
It will be the biggest test of Parker's short career, which has yielded a perfect 7-0 record, and Klitschko has sparred with Williams in the lead-up to his own bout.
Williams (36-13-2) is a durable fighter and the 1.92m Parker will have to use his superior size and quickness to look for an advantage against the Bahamian journeyman.
"I think Joseph Parker is going to face a very experienced and strong fighter in Williams," Klitschko said. "Joseph is going to have a great challenge in the ring. A very great challenge in the ring."
Parker is being pushed along at a steady rate by his handlers who believe further exposure on the world stage will be good for the 22-year-old.
Klitschko has seen it all during a lengthy stint at the top of professional boxing and said Parker needed to find his own path in the sport.
"I can speak a lot and I can say a lot of things but you have to gain your own experience because, at the end of the day, you are going to be alone in the ring. What and who is going to say what? You have to face your opponent and be OK with yourself," Klitschko said.
"Definitely sometimes during the fight you've got to challenge yourself because it's going to get tough and sometimes you have to get up from the canvas and continue to fight to be successful and win it. It doesn't matter what I'm going to say. Just stay focused and be really obsessed with what you're doing and be in love with that because if you don't like what you're doing you will never have success."
Klitschko acknowledged Parker had someone he could attempt to mimic in fellow Kiwi David Tua but said an individual's desire would define how far they could go.
"I think Joseph has the example with David Tua and David was an amazing fighter. I think there are a lot of examples in the division and history that he can take, not just in his corner of this planet but I think that anyone can do it. Anyone can make it.
"At the end of the day, it's face-to-face with another opponent in the ring and the stronger opponent is going to win but there is a lot of tools to take care of and, the harder the preparation, the easier the fight is; so prepare hard and then your fight is going to be relatively easy."