Former sumo grand champion Akebono died in early April of heart failure, the sport's governing body said Thursday. He was 54.

Akebono, who hailed from Hawaii and became the sport's first foreign-born yokozuna in 1993, had been in a Tokyo hospital. The 11-time grand tournament winner helped fuel a sumo boom in the 1990s, engaging in great battles with hugely popular brothers Wakanohana and Takanohana.

"He was a rival. He was a friend. The friend with whom I shared joys and sorrows has departed," Wakanohana, now Masaru Hanada, said in a blog post. "It's so sudden that I can't find words for his departure."

Akebono is pictured holding the Emperor's Cup after winning his first major championship as a sekiwake at the Summer Grand Sumo Tournament at Tokyo's Ryogoku Kokugikan in May 1992. (Kyodo)

Akebono, Wakanohana and Takanohana all made their ring debuts at the 1988 Spring Grand Sumo Tournament, and all reached sumo's highest rank, yokozuna.

At over 2 meters tall, Akebono was scouted and trained by former sekiwake Takamiyama, also from Hawaii.

While still an active wrestler, Akebono, whose real name was Chad Rowan, gained Japanese citizenship and took the Japanese name Taro Akebono in April 1996.

File photo shows yokozuna Akebono performing a ring-entering ritual during the Kyushu Grand Sumo Tournament at Fukuoka Kokusai Center in Fukuoka in November 2000. (Kyodo)

"I was deeply saddened to learn of the passing of Akebono, a giant in the world of sumo, a proud Hawaiian and a bridge between the United States and Japan," U.S. Ambassador to Japan Rahm Emanuel said in a statement.

Akebono "opened the door for other foreign wrestlers to find success in the sport," Emanuel said. "Throughout his 35 years in Japan, Akebono strengthened the cultural ties between the United States and his adopted homeland by uniting us all through sport."

He retired after the 2001 New Year Grand Sumo Tournament and became a sumo stablemaster, or trainer.

After that, Akebono went on to fight in kickboxing, mixed martial arts and professional wrestling.

File photo shows sumo grand champions Akebono (R) and Takanohana performing the rare sandangamae ceremony at Tokyo's Ryogoku Kokugikan in February 1995. (Kyodo)

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