What to do, what to do!

I one of my sites does an online league for Madden football game. The Story of the problem: When a user reports a game that is played, the winner reports the game by choosing his name from a drop down selection box and also choses the loser from the selection box, he enters his password and the game is reported. The Problem The problem is that abusers of the site will report games that they have not played and screws up the stats of the players that he supposedly played against. Now, the ultimate solution would be to have a way where when the winner reports the game it should also be authenticated by the loser as well. So you would have two people reporting in order for the game to be actually recorded in the database. I am asking You All Knowing Ones what would be a solution to this and how would I implement it? here is the site http://madden.williamsen.net I disabled the report feature because of the abuse, now they have to go through me and I have to manually do it