McFadden contributed a significant number of points and in 1946–47 he was traded to the Buffalo Bisons of the American Hockey League.
After averaging over a point with the Bisons in the AHL, he was signed to the National Hockey League by the Detroit Red Wings during their playoff run in 1946–47.
The Red Wings ended up being beaten by the Toronto Maple Leafs in five games, but McFadden's two points during the playoffs helped give him another chance on the roster for next season.
McFadden ended up scoring 24 goals during his rookie season and this helped him win the Calder Memorial Trophy.
On August 20, 1951, McFadden was traded to the Chicago Black Hawks with teammates George Gee, Max McNab, Jimmy Peters, Clare Martin and Rags Raglan in exchange for $75,000 and future considerations.