I think that was during the Diamond/Pearl series.
Some random dude just happened to have legendary Pokemon on his team and that basically gave him an automatic win in the tournament. We never heard of him after that.
At least this time around it's against a character who was previously established in his own mini series and had gueast appearances where he encountered Ash throughout the main series. And Ash got to fight against Alain's entire team instead of just barely being able to take out two of them.