well, in the comics, the same thing that happened to juggernaut (in the cartoon) happened in the comics. the reason they replaced firelord is because the writers of the cartoon felt that firelord wouldnt be recognized as a powerhouse. so they substituted to present gladiator as this unimaginably powerful force. whom got trashed by phoenix 30 seconds later.
so in the comics, i believe juggernaut WOULD win. he was simply put in at last second for popularity purposes (for some reason marvel vs. dc comics are ringing a bell).
later in the comics, rogue punchs gladiator and he fly's off screen. rogue couldnt do that to juggernaut on his best day. rogue went toe to toe with gladiator every time they met in the series, but somehow she knows that she's no match for juggernaut???