Terukuni, Yokozuna or Grand Champion of the Western Camp, was the big upset in Sunday's sumo tournament at the Kokugikan Amphitheater when the behemoth wrestler was thrown for his first defeat on the fifth day of the summer match by Matsuuragata of the Eastern Camp, who achieved the great feat with an upper-hand throw. Terukuni is the first of the four Grand Champions to receive the 'black mark' this season, which is to continue for 15 days.