• Mexican sure he can defeat Briton again in Riyadh in December • Ruiz: ‘I don’t want just 15 minutes of fame, I want it to last’

Andy Ruiz Jr has warned Anthony Joshua he will be faster, leaner and much better prepared for their controversial rematch in Saudi Arabia in December – and he does not intend for his “15 minutes of fame” since winning the world heavyweight title to come to an end.

Ruiz stunned the world by stopping Joshua in June to claim the WBA, IBF and WBO titles and has since bought himself a new house and a Rolls-Royce. But the 29-year-old Mexican insists that the hunger still burns inside him, and that he is intent on proving everyone wrong for a second time.

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“I know Anthony Joshua is coming hard, and I know he is going to be preparing really good,” Ruiz said in a press conference in Diriyah, on the outskirts of the Saudi capital Riyadh.

“But so am I. I’m really hungry. A lot of people saying that I’m not training, that I’m not taking it serious. Come on, I got all these belts. There’s a lot of responsibilities to this. And I’m going to win here in the same fashion as I did on 1 June. And I’m going to prove everybody wrong.

“I don’t want to just have 15 minutes of fame. I want it to last. I want to be a champion for more years. He’s going try to try to take these belts but we’re going to be training really hard for 7 December.”

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Ruiz admitted he was likely to face a tougher test in the rematch in Saudi Arabia, which has been criticised by groups such as Amnesty International because of the country’s appalling human rights record. But the Mexican also pointed out he would be much better prepared too given he only had five weeks’ notice for the first fight.

“He’s more hungry,” Ruiz said. “He wants his belts back. I want to train even harder, you know, because he’s training even harder too. I only had a month and a half to train for the first fight. This time we have a whole camp so it benefits me as well. It’s going to be an explosive fight, two big heavyweights punching each other in the face. It’s going to be exciting.”

Joshua, meanwhile, promised that Ruiz’s reign would be a short one. “I’m really looking forward to the challenge,” he said. “Andy is the champion right now, but that will last until 7 December until he has to put his titles in the air. Two warriors will go to war, and the best man will walk out victorious.