Knoke represented Australia at the 1964 Summer Olympics (Tokyo), 1968 Summer Olympics (Mexico City) and 1972 Summer Olympics (Munich). In Tokyo, on 16 October 1964, he was placed fourth in the 400 metre hurdles final behind Rex Cawley of the United States of America, John Cooper of Great Britain and Salvatore Morale of Italy. He attended the 1962 British Empire and Commonwealth Games, 1966 British Empire and Commonwealth Games, 1970 British Commonwealth Games, 1974 British Commonwealth Games and the Pacific Conference Games twice.