Japan's Ryota Murata won the WBA middleweight world title on Sunday that many thought he was wrongly denied in May, defeating France's Hassan N'Dam by technical knockout.

Murata, a gold medalist at the 2012 London Olympics, suffered a controversial loss to N'Dam on May 20 that saw two of the judges suspended for their scoring the fight in favor of the Frenchman.

Although the first two rounds at Tokyo's Ryogoku Kokugikan were slow and deliberate with fewer punches connecting than clinches, Murata increased the tempo from the third round and from the fourth round N'Dam's legs began to look rubbery and he had trouble moving away when Murata came at him.

After dominating the fight for five straight rounds, N'Dam's corner threw in the towel before the start of the eighth round.

"This victory was for everyone," Murata said. "The hard part starts after I win the belt. It was the same with the Olympics. Getting there was the easy part, moving forward after that was the hard thing."

Murata becomes only the second Japanese to win a world middleweight crown after Shinji Takehara in 1995 and the nation's only Olympic medalist to win a world title.

"I hope this inspires those (in Japan) who love boxing," Murata said. "I hope they aspire to be middleweight champs and be stronger boxers than I am."

Before Murata's fight, Daigo Higa easily won the first defense of his WBC flyweight crown in a seventh-round technical knockout of Frenchman Thomas Masson.

Masson, the fifth-ranked challenger, seemed intent to cover up so Higa would punch himself out early and he could go for the knockout. But Higa showed no signs of tiring and no knockout opportunity presented itself.

Instead, Higa continued to batter away with uppercuts and hooks. The Frenchman suffered a cut around the right eye and slipped to the canvas in the seventh for the fight's first knockdown.

"The first title defense is said to be the hardest," said the 22-year-old Higa. "It seemed like I was never going to knock him down, but I finally managed that."

Higa maintained his perfect record, improving to 14 wins -- all by knockout.

Earlier, Japan's Kenshiro Teraji, who fights under the name Ken Shiro, defeated Mexican Pedro Guevara by a 2-0 decision to defend his WBC light flyweight title for the first time.

"This is a relief," Teraji said. "I wanted to put him on the canvas, but he's strong, and I did not train hard enough."

Teraji improved to 11-0 with five wins by knockout, while Guevara fell to 30-3 with one draw.