Through his first 12 professional fights Japan's Ryota Murata is rather untested, but that will change when he faces battle-tested Hassan N'Dam for a vacant secondary middleweight world title on May 20 at the Ariake Coliseum in Tokyo.

The fight, announced Monday by Murata co-promoter Teiken Promotions, will be part of a world title tripleheader, but Murata, one of Japan's most popular athletes, will headline against N'Dam.

"I've started sparring already in training and it is going well," Murata said at the news conference in translated comments. "I originally started boxing to see how good of fighter I was. If I am able to defeat this opponent, I can confidently say that I am a good fighter. I am looking forward to this fight."

The 31-year-old Murata (12-0, 9 KOs), who is also promoted by Top Rank, won a 2012 Olympic gold medal for Japan and has been heavily hyped since his 2013 professional debut. But he has yet to face anyone close to the caliber of N'Dam.

"Because I am a gold medalist, I have had so much support from so many people," Murata said. "I want to win this fight for all them as my gratitude for their support and kindness. The key for me to win is to fight with what I do well.

"I believe what makes my boxing style exciting is moving forward and throwing punches. We will see if this style will prevail. I expect this fight to be a tough fight. The opponent is type of fighter who can be knocked down four or six times in a fight, but take the remaining rounds on points."

Indeed, N'Dam (35-2, 21 KOs), 33, a Cameroon native fighting out of France, lost his middleweight world title by unanimous decision to Peter Quillin in 2012 in a fight in which Quillin knocked him down six times in an otherwise competitive fight.

N'Dam has won four fights in a row since getting knocked down four times in an otherwise competitive decision loss to David Lemieux for a vacant world title in June 2015. In his last fight, in December, N'Dam obliterated then-undefeated Alfonso Blanco in 22 seconds, knocking him out cold for the 2016 ESPN.com KO of the year, to win an interim title.

"I think that Ryota Murata is a very effective fighter and he proved it as an amateur when he became Olympic champion," N'Dam said. "I think he's going to be a great opponent but I will be -- and I've always been -- ready for great outings, so this fight will be a war because I'm not ready to let my title go anywhere."

N'Dam holds the WBA's interim 160-pound title, but that will be vacated and he and Murata will vie for the regular belt. When "super" titleholder Gennady Golovkin outpointed "regular" titleholder Daniel Jacobs to retain his unified belts on March 18, the regular title became vacant.

Murata said part of his excitement about participating in the fight is because two of his favorite fighters are former WBA middleweight titleholders.

"I am a fan of Felix Trinidad and Bernard Hopkins and the belt I will be fighting for is the same belt that they had," Murata said. "This does not make me a boxing great like they are if I win this belt, but I am fortunate to be able to fight for the belt they held."

In another world title fight on the card, flyweight titlist Juan Hernandez Navarrete (34-2, 25 KOs), 30, of Mexico, will make his first defense when he meets fast-rising mandatory challenger Daigo Higa (12-0, 12 KOs), 21, of Japan.

In the other title bout on the card, junior flyweight titleholder Ganigan Lopez (28-6, 17 KOs), 35, of Mexico, will make his second defense when he faces Ken Shiro (9-0, 5 KOs), 25, of Japan.