In chapter three, you will be faced with a tournament in Lucca. Now you can win it or loose it, it's up to you but the prize is worth it and WAY easier to get at this point. In the finals of the tournament, you have to battle it out with Shinra, the human dictionary for the Lady Luck Sphere. You can get it in later chapters but he's tougher.

You need to win THREE matches in order to move to the finals and defeat Shinra. Practice makes perfect! Oh and by the way:

You can SAVE after two matches at the stadium. Makes life WAY easier when you have to restart ten billion times to defeat evil Shinra.