i do believe this is a hack now, as i have witnessed it. my brother just played a series in which he won both games. the first game was tight and the other player was competitive, 3-1. the second round my brother handed him is own, and was at a 7 0 lead. the guy then began letting my brother score any way hed like, then after it being 10 -0, my brother let him take some points in the game. later to check the leaderboard, we found that my brothers score is plus 1 loss, and minus 4 points. his record is now 1-2 with 10 points when it was, before winning these two games 1-1, with 14 points.
its very odd, and im guessing it must a hack, or some MAJOR glitch in the online play system.