Vorontschichin, who started for the Burevestnik Moscow, made his first international appearance at the 1962 Winter Universiade in Villars-sur-Ollon . There he won the gold medal over 11.5 km. At the Olympic Winter Games in Innsbruck in 1964 , he won over 30 km and the bronze medal with the relay. He also achieved 11th place over 50 km and seventh place over 15 km. At the 1964 Winter Universiade in Špindlerův Mlýn , he won gold with the relay and over 15 km. In 1966 he won the Soviet championships with the relay and the Winter Universiade in Sestriere over 15 km and with the relay. The following year he was third in the Svenska Skidspelen over 30 km. At the 1968 Winter Olympics in Grenoble , he came in 31st place over 50 km. After his active career as a cross-country skier, he coached the Soviet women's team and later the Soviet men's team.