On January 27 1965, Sylvanus Dung Dung joined the army and also played 8 test matches against Holland (1977-78), 4 test matches against Pakistan (1978), and the 4-Nation Quadrangular held in Kuala Lumpur (1980). He delineated Bihar between 1977 and 1981 and Services in the Rangaswami Cup, the national hockey championship. He retired in the year1988.
An experienced person right back, successfully coached the Central Command team from Lucknow to the four sequentially triumphs in the Army hockey championship. It lifted up his confidence level and he declared that no NIS coach could match his skills: "My applications for coaching are being turned down as I am not a product of the NIS. The authorities do not understand the difference between an Olympian and a common coach.