When you are facing a strong opponent, all people will think that you will lose and the other person will win and it will be a cakewalk for the opponent. When the actual game starts you may be able to win it. It is a surprise win and won by underdogs. But you have given a very tough fight stood almost in the game till the last moment and the opponent starts worrying and finally by a small margin if the other person wins, people will start saying he won but the moral victory to you only. As you have brought him almost to the face of defeat morally you have won the game. This is how they use that word. In fact real victory is different from victory.