TOKYO, Jan 24, Reuter - Japan's national sport of sumo, in which obese men throw each other around on a mound of earth, gained a new champion on Sunday with newcomer Asahifuji scoring a surprise win in the first tournament of 1988.

The 27-year-old Asahifuji, elevated to the olympian rank of champion only late last year, clinched the victory by heaving long-time sumo king Chiyonofuji out of the ring after an action-packed 10-second grapple.

The victor's prizes included the Emperor's Cup, 10,000 rice cakes, a year's supply of petrol and a vase from the Hungarian Embassy, plus an undisclosed, but large, sum of money donated by major Japanese corporations.

The win climaxed 15 days of competition in which quivering mountains of near-naked flesh squared off against each other on national television every afternoon.

An out-of-breath Asahifuji, asked how he felt about his victory, told reporters: "I don't know," thereby maintaining the time-honoured tradition of inarticulateness among sumo wrestlers.

It was a rare defeat for Chiyonofuji, 32, known as "the Wolf," who has won half of the more than 40 tournaments in the past seven years.

In the sumo world of obesity, Chiyonofuji, with his lean, mean physique is something of an exception, and a great favourite with the ladies. "He's got a great body," said one female fan.

On Saturday, the Wolf was also beaten by the grossly fat Hawaiian Konishiki, who weighs in at 248 kg (545 pounds).

Konishiki, 23, known to his fans as "Sally," is the fattest wrestler ever to enter the professional sumo ring, experts say.

Six sumo tournaments take place each year, each 15 days long. A bout between two men wearing nothing but over-sized silk g-strings generally lasts 10 seconds at most and is often over in only two or three.

The game dates back into the mists of Japanese history, a test of strength surrounded by centuries of religious and imperial ritual.

But in the end, it comes down to fat men throwing each other around a ring.

Combatants are not allowed to punch or deliver karate chops and kicks to their opponents ample bellies and above are forbidden.

That leaves pushing, slapping, heaving and tripping as the main weapons in the sumo wrestlers' arsenal. However, all combatants are immersed for years in tradition and ritual, so sumo is probably one of the world's most foul-free games.

The tournaments, all televised live, absorb the Japanese nation to an extent only rivalled by baseball -- last March, a parliamentary budget debate was delayed so as not to clash with a particularly enthralling sumo bout.