The California man has stepped into the breach after original challenger Jarrell Miller failed multiple drugs tests, and can now create history by becoming Mexico’s first ever Heavyweight ruler by upsetting unified champion Joshua on his big US debut.

Ruiz is being overlooked by many, but the 29-year-old is relishing being the underdog for his “dream opportunity” and believes being written off could work in his favour as he looks to become a Heavyweight champ at the second time of asking.

“It just gives me more motivation all the guys talking crap,” said Ruiz. “I don’t know if they are mad because I have got this opportunity, but I don’t have anything bad to say about anyone, I talk in the ring with my fists. I’m so mentally strong and prepared for this fight that I don’t care what people have to say.

“A lot of people underestimate me, like I said, the way I look, my appearance, but as soon as they see me throw punches, I’m going to pull out the upset. This is what I have worked for my whole life, I’m here to take what Anthony has. I’m ready to shock the world.

“People will see what I can do. It’s going to be an all action fight, with two big guys punching each other in the face, hard. I’m in this to win it. Everyone else that has fought him has lost before they get in there, I’m not thinking like that, and that’s the difference.

“The most important thing is to win and prove to the fans that I belong at this elite level. I’m not going to chase the KO but I know that it’s there if I execute my combinations. I’m feeling good and ready, AJ hasn’t boxed for nine months and I’m sharper than ever and very motivated.”

“He’s big, but the advantages I have are in speed, movement and coming forward. Everyone AJ fights is scared. I’m not scared of anyone apart from the man upstairs. There’s a lot of doubters out there but I don’t care, they only give me more motivation and confidence.”

Joshua and Ruiz collide on a huge night of action at Madison Square Garden with Irish sensation Katie Taylor clashing with Delfine Persoon for the undisputed Women’s World Lightweight championship, Callum Smith defending his WBA World ‘Super’, WBC Diamond and Ring Magazine Super-Middleweight titles against Hassan N’Dam, Josh Kelly making his US debut as he defends his WBA International Welterweight title against Philadelphia’s Ray Robinson, Joshua Buatsi defending his WBA International Light-Heavyweight title against Marco Antonio Periban, Chris Algieri defending his WBO International title against Britain’s Tommy Coyle in a crunch Super-Lightweight showdown, Olympic bronze medallist Souleymane Cissokho taking on Mexico’s Vladimir Hernandez, Texas Middleweight Austin ‘Ammo’ Williams fighting in his second pro contest and LA Middleweight Diego Pacheco looking to move to 4-0.