In February 1972, then US president Richard Nixon made cold war history by visiting China. Tomorrow, the goalkeeper of Japan's soccer team, Yoshikatsu Kawaguchi, has a chance to go one better. Sport has long played a role in settling diplomatic disputes. For decades, the Olympic Games have brought together foes on the sporting field as a precursor to having them meet around a negotiating table. When it came to relations with the US, China in 1971 turned the equation around and began with a table tennis table. At the World Table Tennis Championships in the Japanese city of Nagoya, its players invited the Americans to visit. So began what became known as 'ping-pong diplomacy'. The US team accepted the invitation and shortly after their return home, former secretary of state Henry Kissinger secretly visited Beijing. Seven months later, Nixon made his groundbreaking trip, during which mainland relations were resumed for the first time since the founding of the People's Republic in 1949. On April 12, a plane carrying the national table tennis team landed in Detroit for a 10-city tour, cementing the new-found ties. The formula became a staple of diplomats trying to forge or repair relations. Whatever the discipline - athletics, gymnastics, cricket, golf, and scores of others - sport was seen as being above politics and therefore a perfect starting point to engendering diplomacy. Which brings us to the Asian Cup soccer tournament. The event reaches its climax at the Worker's Stadium in Beijing tomorrow night, when China and Japan meet in the final. The national team, undefeated in 19 games, has reached the final for the first time in 20 years. It will be Japan's third appearance in 12 years. There is intense rivalry, and Chinese spectators have let their passions boil over several times while watching Japan play. Japanese officials are so worried about the hostility at the final that they have appealed for calm in the name of fair play. Chief Cabinet Secretary Hiroyuki Hosoda announced on Wednesday that his country had made a formal complaint to China over the incessant booing by the Chinese spectators. He said: 'It's a sporting exchange - this should not fuel anti-Japanese sentiment.' Such behaviour by Chinese fans, while not condoned, is understandable given the generations of hatred. The atrocities committed by Japanese troops - starting with the occupation of Manchuria in 1931, continuing through the full-scale invasion of China six years later, and ending only with Japan's surrender at the end of the second world war in 1945 - cannot be easily forgotten. Japanese Prime Minister Junichiro Koizumi has not helped heal the wounds. He has been denied an official visit to China for making yearly visits since 2001 to the Yakazuni Shrine to his country's war heroes. Each visit has been met across East Asia with protests. Japan can give as much financial aid as it likes to countries it invaded and caused misery in during the first half of the 20th century, but it can never win the respect it desires if its leaders trample on sensibilities. But where Mr Koizumi has damaged his nation's hopes of being truly accepted among East Asians, goalkeeper Kawaguchi has the chance to make amends. For now, it is unclear whether China's injured striker Hao Haidong will play. But whether it is Hao, a replacement, or fellow forward Shao Jiayi with the ball and charging for the goal tomorrow night, Kawaguchi has a diplomatic duty to stand rock still in the goalmouth and do nothing. His teammates would likewise do well to feign leaden feet, being dazzled by the floodlights, or simply being put off by the incessant booing. They need not feel ashamed at losing. If questioned, they can hold up their heads proudly and say that their actions were in the name and spirit of soccer diplomacy. Peter Kammerer is the Post's foreign editor