Boxing: Joseph Parker takes new jab at Anthony Joshua's fitness

Anthony Joshua of Britain and New Zealand's Joseph Parker. Photo / AP Photo

Joseph Parker and his team have moved on from the sledgehammer approach of highlighting Anthony Joshua's "glass jaw" to a more subtle but no less deliberate questioning of the Englishman's fitness.

The impressively-built Joshua tired in his last fight - a stoppage victory against former Parker foe Carlos Takam - and the latest jab in the build-up to the world heavyweight unification fight in Cardiff on March 31 is another designed to create more doubt in Joshua's mind.

Even before the 10th-round TKO at the Principality Stadium last October - a home-town decision by the referee as far as many boxing experts are concerned - Joshua looked sluggish. In the later rounds he was clearly breathing hard.

He later admitted that the late withdrawal through injury of original opponent Kubrat Pulev affected him and that he would make changes to his next conditioning programme but Parker and trainer Kevin Barry have wondered aloud whether that will be enough.

"My body type, even though it's not really muscular, [has] worked for us," Parker told Sky Sports UK. "We know that we can fight hard from round one to round 12. It's all that matters."

Joshua, 28, is hard at work at his camp in Sheffield and has posted pictures on social media of his heavily-muscled body.

Parker, laughed at by Joshua for his "pie-eating" physique, said: "When you watch him, when you see all the training, it's like they are doing all this new training and it looks really hard, and it looks intense, and it looks the type of training that will prepare you for 12 rounds.

"But, in saying that, just maybe their team need to work on a few things. We know that our team has a good structure and a good training programme that will allow us to fight 12 rounds, if we need it.

"But I'm not sure why he tires, that's something he has to sort of figure out."

Parker is now into the sparring phase of his preparation at his Las Vegas base, with Barry telling the Herald recently that the weight put on following his points victory over Hughie Fury in Manchester last September is coming off and that he was looking as sharp as ever.

He and Barry would have liked to have finished his recent fights in more spectacular fashion, but going 12 rounds against Fury and Razvan Cojanu last year, and Andy Ruiz and Carlos Takam in 2016, have at least shown Parker has good endurance.

Many believe the Joshua v Parker fight will go to the late rounds, and it's here that the New Zealander could have an advantage.

"I see videos posted everywhere of him [Joshua] doing the most sophisticated, new-age training methods that man has ever seen and, yet he's looked very tired in his last couple of fights," Barry told Sky Sports UK.

"Every time he's been asked to go on to the later rounds, he's really struggled so that's a question for his training staff.

"He wouldn't want to be slowing against Joe, because I can promise you this. Joe will be coming on in the later rounds."

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