For unified heavyweight champion Anthony Joshua to truly carry the moniker of the biggest star in global boxing, the native of Great Britain will first need to prove he can conquer America. 

Joshua's U.S. debut will take place Saturday inside New York's hallowed Madison Square Garden (DAZN, 9 p.m. ET) when he defends his IBF, WBA and WBO titles in a long-awaited British invasion for the 29-year-old star who won gold at the 2012 London Olympics before winning his first world title four years later in just his 16th pro fight. 

But instead of facing unbeaten WBC champion Deontay Wilder in a fight that is arguably the biggest the sport can make, Joshua (22-0, 21 KOs) will take on late replacement Andy Ruiz Jr. (32-1, 21 KOs), a quick-fisted Mexican-American fighter who replaced Jarrell "Big Baby" Miller four weeks ago following a trio of failed drug tests. 

No, this isn't the battle for the undisputed championship that fans have lusted after for three years only to become increasingly frustrated at the public soap opera of failed negotiations between the two. Yet Saturday's fight should be an important step in getting there as AJ departs the friendly confines of his sold out soccer stadiums (including an attendance of 90,000 against Wladimir Klitschko in 2017) to test his brand on American soil. 

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There's certainly no doubt when comparing the name recognition and selling powers of both fighters in their respective home countries that Joshua, a national hero amid a fight-crazy culture, is the king. Despite Wilder slowly gaining traction with knockouts akin to his scary one-punch finish of Dominic Breazeale two weeks ago, the 2008 U.S. Olympic bronze medalist has had trouble becoming a household name competing against team-sport stars. 

Thanks to boxing politics, however, in which both fighters operate on separate sides of the street promotionally and in terms of their broadcast homes, the main reason why Joshua-Wilder continues to marinate as negotiations stumble is because both sides refuse to play the B-side of the promotion. So for a fight this big to be made, in which all parties -- particularly the networks -- would be willing to join hands, the fight needs to be as lucrative as possible. 

What could certainly go a long way in making that goal become a reality is Joshua, despite being the bigger star globally, truly establishing himself within the American sporting culture, where unlike in the U.K., fans are much more conditioned to pay the exorbitant pay-per-view prices to see dream fights like this take place. 

Wilder (41-0-1) was criticized by some on Tuesday for public announcing his next bout would come in September against Luis Ortiz in a rematch of their dramatic 2018 bout in which Wilder rallied to win by 10th-round TKO. Instead of waiting to see the results of Joshua-Ruiz and entertaining an immediate offer, Wilder's decision pushed off the possibility of a Joshua fight until at least 2020. 

Through it all, Joshua continued to preach patience that the fight will happen soon enough. 

"I can't control the division," Joshua said during Tuesday's media workout. "I think people maybe assume that we were the ones that were dodging people and I think [other heavyweights] have done a great campaign to make a name off the back off our success on this side of the pond. Yet with all that talk and hearsay, none of them have stepped up. What can I say? Talk is cheap."

While the recent heavyweight renaissance has seen the division sprout a handful of exciting and hungry fighters with equally large personalities, many of them -- including Wilder and Joshua -- have been forced to sort of learn on the job and see their first major tests come as champions. That's partially why the 29-year-old Joshua hasn't let the delay in fighting Wilder affect him emotionally. 

"Believe me, I would rather fight Wilder in two years," Joshua said. "Because I know I will get better all the time. And at 33, he's the one who's getting older."

Boxing fans may not be interested in another stubborn build like the five-year odyssey it took to finally see Floyd Mayweather-Manny Pacquiao come to fruition in 2015, yet both unbeaten heavyweights remain confident that all roads lead to each other. 

"I'm not overlooking Ruiz," Joshua said. "It's fairly simple, it's not complicated. [Wilder] has got the belt I want, I've got the belt he wants. He has been calling my name out for the last year or so, I've been calling his name. Whenever he's ready because I'm definitely ready."

"The pressure is on. I've got to send a message [against Ruiz]. Hello America, we're here. We are here not to take part but to take over."