The YuYu Hakusho anime adaptation by Studio Pierrot had begun airing in North America on Cartoon Network in 2002, where it proved popular on the afternoon Toonami block. In July 2003, Atari established a publishing agreement with Funimation Entertainment, the English licensor of the anime adaptation series. Prior to this deal, games based on the series had never been made available to English-speaking audiences in North America, Europe or Australia, although Atari had previously published games based another successful Funimation property, Dragon Ball Z .
Atari released its first game Yu Yu Hakusho: Spirit Detective for the Game Boy Advance in December 2003 and announced Dark Tournament just before the Electronic Entertainment Expo in May 2004. Yu Yu Hakusho: Tournament Tactics was also released in 2004 for Game Boy Advance.
Source: Wikipedia, "Yu Yu Hakusho: Dark Tournament", available under the CC-BY-SA License.