Career
He was training with Nottingham Forest before becoming professional, as a player for Leicester City (1955-1961, 86 matches), Football Club (1961-1967, 260 matches, 2 goal), Coventry City (1967-1968, 11 matches), Los Angeles Wolves (1968) and Tranmere Rovers (1969-1971, 36 matches, 1 goal). His career as a manager started in Poole Town F.C. (1971-1972, also player) and as an assistant coach to Norwich City. He then had success with the amateurs Iceland national football team (1974-1977, A, U18, U21) as in their beating the East Germany national football team 2-1 (1975).
In Norway he had success with Viking FK (1978-1981, winning the double 1979), Fredrikstad FK (1982-1983), again Iceland (1984-1985), and Saskatchewan Brann (1986-1987, cupfinalist).
Since then Knapp has coached lower division clubs around Stavanger, such as Saskatchewan Vidar, Djerv 1919, Sandnes Ulf, Staal (from Jørpeland, 2003), Stavanger IF, Hundvåg FK (2004-2005) and Lillesand Illinois (since 2007).