By Keith Idec

Joseph Parker is undefeated, owns a heavyweight title and has shown a reliable chin since he turned pro 5½ years ago.

According to Anthony Joshua’s trainer, however, nothing has prepared Parker for what he’ll encounter Saturday night in Cardiff, Wales. Rob McCracken contends New Zealand’s Parker isn’t ready for what awaits him in his 12-round title unification fight against England’s Joshua at Principality Stadium (Sky Sports Box Office; Showtime).

“[He’s] an unbeaten opponent, so he doesn’t believe he can lose,” McCracken said Tuesday as part of a final press conference to promote the Joshua-Parker bout. “But, you know, being fast and being calm and relaxed, and all of that you need going into a big fight, it doesn’t prepare you for getting into a ring with Anthony Joshua. It really doesn’t. And, you know, not just the size of him – he’s very imposing in the ring – but he hits you and you don’t know why you’re getting hit. And I think you’ve seen that in all of his contests up to date.”

The 26-year-old Parker (24-0, 18 KOs) won the then-vacant WBO belt by edging American Andy Ruiz (30-1, 20 KOs) by majority decision in December 2016. Following that narrow win, he made two title defenses – a unanimous-decision victory over Romania’s Razvan Cojanu (16-3, 9 KOs) on May 6 and a majority-decision defeat of England’s Hughie Fury (20-1, 10 KOs) on September 23.

Parker wasn’t particularly impressive in any of those three championship matches. Joshua, meanwhile, displayed legendary determination and toughness in getting off the canvas against Wladimir Klitschko to stop the long-reigning former champion in the 11th round of their unforgettable fight April 29 at Wembley Stadium in London.

“[He fought] Klitschko obviously at the highest level, but you saw how he started and how he finished,” McCracken said. “Had a blip in the middle, but that had to do with getting hit with some really solid shots from a devastating puncher. But Anthony’s in great shape, he’s really looking forward to the fight and he just sees it as another fight on the ladder to becoming the undisputed champion. And that’s the reason why the fight’s taking place. Parker’s the WBO champion, he’s a good fighter, he’s unbeaten and he’s a challenge, and AJ’s up for it.”

McCracken maintains that Joshua (20-0, 20 KOs), who was 27 at the time, fought Klitschko too soon. Joshua’s trainer also acknowledges that what the IBF/IBO/WBA champion learned during that back-and-forth fight has helped make him the best heavyweight in the sport.

“It’s common knowledge I thought it was three fights too early, Klitschko,” McCracken said. “He was using experience and [is] a massive puncher. But I felt if Anthony didn’t make too many mistakes, he could win the fight. And, you know, his desire to win carried him through the middle part. So, you know, he checks all the boxes, really. He can box, he can fight, you know, he’s a devastating puncher himself.

“And he can take a devastating shot, so he’s improving all of the time, he’s learning all of the time. But, you know, he’s already the unified champion, he’s already an Olympic gold medalist and, you know, it’s part of a journey that he sees himself becoming the undisputed champion.”

Keith Idec is a senior writer/columnist for BoxingScene.com. He can be reached on Twitter @Idecboxing.