Joseph Parker admits he has been watching Anthony Joshua’s training techniques, and doesn’t understand why Joshua ‘tires’ in fights, Sky Sports report.

Joshua returned to his base in Sheffield this week as he continues his new training regime ahead of the pairs unification clash at the Principality Stadium in Cardiff at the end of March.

Richard Heathcote/Getty Images Sport

New Zealander Parker however, has been preparing over in Las Vegas, with three world heavyweight titles set to be on the line when both unbeaten fighters meet in Wales.

Parker, 26, has gone the full distance in four of his last six fights and has recently questioned Joshua’s fitness in latter rounds of his previous fights.

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

Kevin Barry, Parker’s trainer, has also added fuel to the fire between the pair by suggesting that Joshua could be forced to endure a late assault if the fight goes that far, due to Parker’s proven fitness in his previous bouts.