The most dominant female athlete in Rio is up for debate, but none of Simone Biles, Katie Ledecky or Serena Williams can match the Olympic longevity of a pair largely unknown to Americans.

Saori Yoshida and Kaori Icho are Japanese wrestlers. And they are perfect at the Olympics. Each competed in the 2004, 2008 and 2012 Games and won gold every time in her respective weight class.

On Aug. 17, Icho will take the mat in the 58kg division, seeking to become the first woman to win an individual-event gold medal in four Olympics. In any sport.

The next day, Yoshida will attempt to reach the same pinnacle in the 53kg division.

Other male athletes are in club four (including Carl Lewis in the long jump and Al Oerter in the discus, with possibly Michael Phelps joining next week), but no women have achieved such success outside of team sports.

“Among women, they certainly rank high,” said Olympic historian Bill Mallon, who further outlined the history Icho and Yoshida could make on Olympstats.com. “The only downside on it is, and I hate to put rain on their parade, is it’s kind of a new sport [women’s wrestling debuted at the Olympics in 2004]. It doesn’t have the levels of competitors that swimming or athletics does.”

Mallon’s pick for greatest female Olympian of all time is German kayaker Birgit Fischer-Schmidt, who won eight gold medals across six Olympics and could have earned more if not for East Germany’s boycott of the 1984 Los Angeles Games. All but two of Fischer-Schmidt’s medals came with teammates.

“The [greatest] woman choice is a hard one,” Mallon said. “It would be incredible, to be the first time women would win the same individual event, four gold medals in a row.”

Yoshida, 33, owns a senior career record of 255-11 over nearly two decades. She’s lost twice internationally, once in 2008 to snap a 119-match winning streak, and once in 2012. She has won 13 straight world championships dating to her first title in 2002.

Icho, 32 and considered less recognizable than Yoshida in Japan, is 222-7 in her career. She went 13 years between defeats (minus a controversial 2007 forfeit) from 2003 to this past January. Icho is a 10-time world champion since 2002, having skipped three world meets.

“They’re legends, absolutely legendary,” said Jordan Burroughs, who in Rio will try to become the first U.S. wrestler since 1992 to repeat as Olympic champion.

Burroughs, who is 28, has a best streak of 69 straight wins in a three-and-a-half-year stretch up to February 2014.

“People think that when my career is done, the culmination of all the things that I’ve done will be legendary, but it’s incomparable to what these ladies have done,” Burroughs said. “I don’t even know what sports you can compare it to. It’s unbelievable.”

In wrestling, Yoshida and Icho are most often compared to Aleksandr Karelin, the Soviet-raised Greco-Roman super heavyweight who won three straight Olympic titles and nine straight world titles until he was shocked by American Rulon Gardner in the Sydney 2000 final.

“Karelin, I think generally people would say he’s the best ever,” said William May, who has written about international wrestling for 30 years, including for Kyodo News in Tokyo. “Comparing him with the women, it’s apples and oranges. … It’s a different sport. But in that universe, Icho and Yoshida will be women’s wrestling’s Karelin. I think that’s probably the only way to explain it.”

They are products of a Japanese women’s wrestling system developed in the 1980s, after the international wrestling federation was scrutinized for a lack of gender equality and encouraged more female participation. While some traditional power nations were hesitant to change, Japan’s federation jumped right on it.

Yoshida began wrestling at age 3, after her father, Japanese national wrestling champion Eikatsu Yoshida, built a dojo in the family living room to teach her and her two older brothers. Yoshida’s father was strict to the point of hitting his wrestlers, but she admired him greatly.

After her third gold medal in London, Yoshida lifted her dad on her shoulders and paraded on the mat.

In March 2014, Eikatsu Yoshida was found dead in his car after suffering a brain hemorrhage. The next week, Yoshida led Japan to a World Cup title, carrying with her a framed picture of her father and a pouch with his ashes.

Yoshida’s toughest matches occurred during her late teens. Countrywoman Seiko Yamamoto won three straight world titles in Yoshida’s division, and beat Yoshida four times, before Yoshida displaced her for good before the 2004 Olympics. Yamamoto is now retired and had a baby with Texas Rangers pitcher Yu Darvish last year.

Icho, from Japan’s northernmost prefecture, is part of a wrestling family, too. Her older sister, Chiharu, earned Olympic silver medals in 2004 and 2008. Her older brother also wrestled.

“Kaori was also 3 years old, 4 years old, when she started following them to the wrestling club,” May said. “A lot of the Japanese wrestlers start young.”

Like most stars in Japan’s unmatched women’s wrestling system, Yoshida and Icho eventually moved to Chukyo University near Nagoya. They trained together for several years before the 2004 and 2008 Olympics.

Tim Foley, senior manager of media operations for United World Wrestling, spent time with both wrestlers in Japan this spring for a documentary film published Wednesday.

The interviews with the wrestlers were done separately.

Yoshida, who slightly tips 5 feet, and Icho, a few inches taller, share sterling records and dancing roles in this Japanese security company commercial, but they are very different in personality.

“Yoshida is this megawatt superstar, household name kind of thing,” Foley said. “Icho is completely anonymous. She chooses to be that way, works on her craft and sticks to that.”

Icho left Nagoya for Tokyo between the 2008 and 2012 Olympics, after taking a one-year break from competition.

“We practiced together and went through tough times together,” Yoshida told United World Wrestling. “But in general, we just leave each other alone.”

Yoshida chuckles before continuing, “I guess we’re kind of like couples. But it feels good to work towards a common goal with her.”

Those who have followed Yoshida say she is consumed with winning, with chasing records. She seeks attention — such as in a commercial as a Power Rangers-like character with lasers beaming out of her eyes, or singing in a music video — and will appease the Japanese wrestling federation’s sponsor requests.

“[Icho] isn’t as out there about winning as Yoshida, who is just out there like, I’m just going to kill everyone and leave,” said American Adeline Gray, the two-time reigning world champion at 75kg. “Drop the mic. That’s pretty much how [Yoshida] gets thing done.”

Yoshida carried the Japanese flag into the 2012 Olympic Opening Ceremony and is the captain of the entire Japanese delegation this year, reportedly the first time a female athlete earned that honor.

“There’s a lot of pressure on me,” Yoshida told United World Wrestling. “It’s a burden.”

In contrast, Icho seeks “inner perfection,” May said.

In Foley’s film, Yoshida is called a celebrity, while Icho is labeled Samurai.

“Of course [Icho] wants to win, but it’s less important than wrestling a perfect match,” May said. “It’s very Zen. And when she’s out there, she’s just on a different planet.”

May said one can see the fear in Yoshida’s eyes if she’s losing late in a match.

Whereas the less-perceptible Icho’s most emotional moment at a competition may have come sitting in the stands, at the 2008 Beijing Olympics. She bawled into her jacket collar after watching her older sister, Chiharu, lose her gold-medal match for a second straight Olympics.

“Icho does not care one bit for records,” Foley said. “She used to care, and then her sister didn’t win in 2008, and it really affected her. She thought, if I only hunt for gold, and I see how much it hurt my sister, maybe I should focus more on the artistry.”

The Icho sisters took a year off after Beijing. They wanted to get away from the pressures of the sport, the attention in Japan. So they traveled to Calgary.

Chiharu ended up retiring, while Icho returned to Japan after skipping two world championships at the height of her career in 2008 (worlds are held after the Olympics in an Olympic year) and 2009.

“It’s not that I don’t like being on TV, but I don’t like my practice time being taken away or to lose time for myself,” Icho said in the United World Wrestling film.

Yoshida and Icho have U.S. connections. They visited the U.S. Olympic Trainer Center in Colorado Springs, Colo., where the Japanese declined American women’s wrestlers’ invitations to go out with them at night, claiming coaches wouldn’t allow it.

Americans have also beaten them.

In March 2003, Sara McMann of Takoma Park, Maryland, drew Icho in the first round of the Klippan Open in Sweden. McMann, four years older than Icho, said she had been battling a sinus infection, but she felt confident. That’s because McMann to this day believes she pinned Icho at the 2002 World Championships, but the referee didn’t see it.

“When I felt her and wrestled her, I felt like I could beat this girl,” McMann, now a UFC fighter, said in a phone interview. “The majority of our matches were one point [margins] or overtime.”

This match wasn’t. McMann won 6-3 and said the key to staying with Icho is to show the Japan star attacks she’s never seen before. The Japanese are excellent at studying film, and Icho is like a grandmaster.

“If I had to pick out one of her strengths, it’s capitalizing on other people’s mistakes,” McMann said. “It isn’t so much exactly what she does. She is very patient. And once she scores on you, you’re down in points and you have to open up even further.”

McMann was the only wrestler to beat Icho for nearly 13 years, until this past January.

In January 2008, Yoshida faced Marcie Van Dusen of Lake Arrowhead, California, at a World Cup in China. Van Dusen was relatively unheralded on the senior international level, with zero Olympic or world championships medals, but she had previously defeated Yoshida in their teens.

Yoshida doesn’t forget losses. In the years before 2008, every time she greeted Van Dusen at a tournament, Yoshida, who speaks little English, would repeat the site of that junior defeat.

“Manchester, Manchester.”

At the 2008 World Cup in China, Van Dusen entered with a strategy not to walk into Yoshida’s signature attack move, an explosive double-leg takedown. It was Yoshida’s primary weapon to beat her previous 119 straight opponents.

“Everybody knows exactly what she’s going to do,” McMann said of Yoshida, “and nobody can stop it.”

Yet Van Dusen successfully countered Yoshida’s double-leg attack for points to secure the upset. The American’s enduring memory of that tournament wasn’t so much snapping Yoshida’s streak, but seeing Yoshida in the hallway at the post-competition banquet.

“Even after a loss like that, I ran into her going to the restroom, she grabbed my hand and bowed and said good job,” Van Dusen said.

Yoshida and Icho are gold-medal favorites in Rio, but each carries doubt.

Experts say Yoshida has lost a step, and that’s critical given explosiveness is her best attribute. Yoshida edged Swedish rival Sofia Mattsson 2-1 in the 2015 Worlds final, after winning 6-0 in their match the year before. Yoshida, at 33, is also dealing with a knee injury and expects Rio to be her final competition, Foley said.

“She’s at the highest level of maintenance,” Foley said. “She’s not working out to get stronger like a 22-year-old. She’s working out to maintain what she has.”

Icho shockingly lost for the first time in 13 years in January, a 10-0 technical fall at the hands of a 22-year-old Mongolian.

“She was a little bit rattled not only by losing, but how bad she lost,” Foley said.

Icho came back to win her next tournament in Poland, where she didn’t face the Mongolian.

“Every time I look at it [the silver medal from January] the feelings of frustration will probably return,” Icho said, according to Kyodo News. “I want to cherish that.”

The active U.S. wrestler who best knows Icho and Yoshida may be Helen Maroulis. Maroulis won the 2015 World title in the 55kg division, which is not an Olympic weight class.

For 2016, Maroulis had a choice — drop down to 53kg (Yoshida’s class), or move up to 58kg (Icho’s class). She chose 53kg.

Maroulis is 0-2 in her career against Yoshida, getting pinned at both the 2011 and 2012 World Championships. But she has also learned from Yoshida’s old rival Yamamoto, who was a USA Wrestling coach for a number of years.

“It maybe looks like this David and Goliath battle,” Maroulis, who trained with Yoshida in Japan and drove to a Drake concert with Icho in Colorado, recently told USA Wrestling. “I’ve been scouting, I’ve been preparing for this, and I think I’m the girl to do it.”

Japan’s results in Rio across all sports will be scrutinized as the 2020 Tokyo Games approach. The nation boasts dominant figures in gymnastics (Kohei Uchimura) and swimming (Kosuke Hagino), too.

But Foley’s opinion is that Icho and especially Yoshida have earned a place among the nation’s most famous baseball players, figure skaters and sumo wrestlers.

And if Icho wins gold and continues another four years (unknown at this point), the Samurai could become the hometown face of the Olympic host nation in 2020.

Nick Zaccardi is NBCSports.com’s OlympicTalk editor. He has covered three Olympics, major international sporting events and college and professional sports in the U.S.
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