I think it was a tournament to open the season. Kinda in reverse, I guess. I think the tournament you're forced to play is some special one to celebrate Yu Yevon or something. I don't know, it's been ages for me, roll with it

FFX has the worst set of mini-games ever. It is sooooo bad. I repeated that forced game like four times to win the cup. And those cutscenes, gosh, I don't think you could skip them either. That took a damn long time.