Why is Manny Pacquiao fighting in Macau? Because of this rising star ...

MACAU – Outwardly, Zou Shiming is an unremarkable man. He's a slender 5-feet-4 and has neither the fierce countenance nor muscular build one would associate with an elite boxer.

He's largely quiet and respectful and does little to call attention to himself.

But Manny Pacquiao would not be headlining a lucrative pay-per-view card in this lavish casino resort were it not for Zou, a three-time Olympic medalist who may be transforming the sport as we know it.

Millions of words will be written and said about Pacquiao and his bout on Saturday (Sunday in China) with Chris Algieri for the WBO junior welterweight championship at the Cotai Arena in the Venetian Macao.

If it weren't for Zou, however, the fight likely would be taking place on the Las Vegas Strip, where for decades the overwhelming majority of major fights have been held.

Ed Tracy, the CEO of Sands China Ltd., the parent company of the Venetian Macao, did not hesitate: Were it not for Zou's immense popularity in China, there would be no boxing in Macau.

"We have to talk about how this all happened and it really happened around Shiming," Tracy said. "You know his story. To have an opportunity to coalesce our boxing program around someone who is a national hero doesn't happen every day. [Top Rank CEO] Bob [Arum] had the foresight to see that and I was happy to go as his co-pilot to push it over the goal line.

"Frankly, this guy has delivered in a way that has really surprised me. He's a great guy; we all know that. Fabulous. He's a hell of a boxer, just starting. Where he goes is yet to be seen. He hasn't disappointed yet and along the way, we're finding other Chinese boxers."

Arum called Zou among the greatest amateur boxers of all-time, noting that Zou won a bronze medal in Athens at the 2004 Olympics and then back-to-back gold medals in Beijing and London in 2008 and 2012, respectively.

He also won a silver and three golds in the world amateur championships.

Roy Jones Jr., the HBO Sports boxing analyst and former pound-for-pound kingpin, gave his stamp of approval to Zou.

"What you saw him do [as an amateur] is incredible," Jones said. "That was a statement about his skills in and of itself."

Zou won his amateur medals as a light flyweight, but is competing as a flyweight as a professional. He'll meet unbeaten Kwanpichit "Mini Manny" Onesongchaigym of Thailand on Saturday's pay-per-view card with a world title shot likely in February if he wins.

His trainer, Freddie Roach, said Zou's progress has been steady, though Zou is relatively old at 33 for a boxer who is just 5-0 as a pro.

Zou regularly spars Brian Viloria, a 2000 American Olympian and long one of the better fighters in the lighter weight classes, at Roach's Wild Card Gym.

There is talk of a Zou-Viloria fight sometime next year, if Zou wins a world title in February.

Roach laughs and said Zou "looked like [crap]," when they first started to work together and said he wasn't certain what he'd gotten himself into by agreeing to train him.

But Zou, who even at the advanced age of 33 for a flyweight, retains his speed and is among the faster men in his division. Roach has been looking to add power to his shots, much like Abel Sanchez has done with middleweight champion Gennady Golovkin, and he's been encouraged by what he has seen.

On Feb. 22 in just his fourth fight, Zou knocked out Yokthong Kokietgym in the seventh round of a scheduled eight-rounder. He's showing progress.

But Roach knows the story. Pacquiao is one of the sport's two biggest stars, alongside Floyd Mayweather Jr., but Zou is the star of this show in this part of the world.

"Without Shiming on the show, there's really no show," Roach said. "He is the draw right now. The Chinese people are starting to get to know Pacquiao because he's fought here before and he's been here a couple of times. The Chinese and the Filipinos are rivals and don't communicate very much and to be honest with you, a lot of the people here have never heard of Manny Pacquiao before.

"It's all Shiming. There is pressure on him, because he's basically carrying boxing in China and helping to build it there. His people know how big he is in China and they wanted him to be the main event ahead of Manny [for his previous fight in Macau against Brandon Rios] until we explained they couldn't do that. But there is a burden on him that not many other fighters have to carry."

Arum said Zou has more endorsements than any boxer he's aware of, including Pacquiao. Zou attended a press event before his workout on Thursday in Macau to announce a deal with Beats headphones.

But Zou could have more if he were looking to make his trunks look like they were designed by someone from NASCAR. In addition to Beats, he's also sponsored by Anta, a sportswear brand that agent Edmund Chu called "kind of like the Nike of Asia."

Zou also appeared in "Transformers: Age of Extinction."

"A lot of brands are looking to associate themselves with Shiming," Chu said. "We're very careful with the brands we associate with now."

Saturday's card will be broadcast in China on CCTV, every regional sports network and on the country's two largest internet portals. Tracy and Arum estimate viewership could reach 350 million.

It's made Shiming one of the best-known athletes in the world, even if he remains an unknown in the West. Boxing had been banned for years in China under Mao Tse Tung and wasn't permitted again until 1986, when Zou was 5.

But boxing hasn't been popular in China until Zou won the gold medal. It's building, though, and Zou is the man leading the way.

He's not letting the pressure bother him.

"It's not a problem," Zou said. "I just fight and do my thing."

Arum, Chu, Tracy and others will worry about the details. But if China ever becomes a legitimate market for major boxing events, the promoters will have the slender and shy flyweight to thank for it.