Challenge of the Samurai. And it was around three-to-three thirty PM, and the channel was UPN 69, right before Duck Tales at three-thirty to four, and then Hercules after that and then Doug after that, followed by two airings of Sister Sister for the 5 PM slot and back to back episodes of Frasier for the Six PM slot.
While I was aware there had been a comic thanks to Pokémon Power, I didn't even know there was a TV show until that day. And it was around Summer 1999.