Japan was mourning Sunday after the death of former sumo grand champion Taiho, who won a record 32 tournaments and became a hugely popular figure in the 1960s when the sport was untainted by the damaging scandals seen more recently.

Taiho, whose real name was Koki Naya, died of heart failure in hospital in Tokyo on Saturday, the Japan Sumo Association said. He was 72.

His death was front-page news in Japan, with the Nikkan Sports daily calling him "the strongest yokozuna (sumo grand champion) in history".

"He was sumo history," former yokozuna Chiyonofuji, whose 31 championships are second on the all-time list, told Kyodo news agency. "That one additional title he won, that was something beyond my reach. It is a measure of his greatness."

Born on the then Japanese-occupied island of Sakhalin off the Russian far east to a Japanese mother and a Ukrainian father, Naya was raised on the northern Japanese island of Hokkaido, reportedly in poverty.

After making his debut in 1956, he won his first championship in 1960 and became the youngest wrestler to reach sumo's top rank in 1961 when he was 21 years old.

He retired from competition in 1971 after a career that saw him twice win six tournaments in a row. He also took eight tournaments with 15 straight wins against no losses and had a 45-match winning streak.

Naya was "a hero in the period of Japan's rapid economic growth in the 1960s", the Tokyo Chunichi Sports commented.

A catchphrase, "Kyojin, Taiho, tamagoyaki", was also coined, putting him among children's top three favourite things, which also included the Yomirui Giants baseball team and a Japanese rolled omelette, a school lunchbox must-have.

After his retirement from the clay ring, Naya founded his own stable. He suffered a stroke in 1977 but recovered and went on to serve in variouos posts in the sumo association.

Sumo's popularity has declined in recent years amid scandals including match-fixing, marijuana use, illegal betting by the wrestlers, and the death of an apprentice due to hazing by seniors at their sumo stable.

The increase in foreign-born wrestlers has also been contentious.

Hawaiian Akebono became the first foreigner to become yokozuna in 1993, followed by four more -- another Hawaiian and three Mongolians. The sport is currently dominated by foreign-born wrestlers with its top rank occupied by two of the Mongolians.

"We live in an era in which it is not easy for us to share common values," the Asahi daily commented. "That may be why we feel nostalgic about 'the Giants, Taiho and rolled omelette.'"