Sport Billy has the distinction of being the last Filmation series sold to NBC, but in fact it was imported, as Filmation had produced it initially for European markets.
Billy (Lane Scheimer, ex-The Brady Kids, Lassie's Rescue Rangers) carries with him an Omni-sack, a size changing gym bag that can be made small enough to carry in Billy's pocket for when he needs it, which seems to be in every episode. He's joined by Lilly (Joyce Bulifant, ex-The Mary Tyler Moore Show) and a dog, Willy (Frank Welker) in his adventures. Since this was meant for European consumption, the primary sport is their version of football----what we call soccer. 26 episodes were produced and aired during one calendar year. NBC aired it initially as a summer replacement, then would bring it back again the following year.
Here's the intro:
What hurt Sport Billy here was where NBC scheduled it---at lunch time. If memory serves, it was in place of either Drawing Power or The Daffy Duck Show, I'm not sure which. As I've oft noted, if it's booked to air at 12, unless it's Fat Albert, it ain't gonna last long. Sadly, the series has not resurfaced on cable in the 30+ years since its debut.