Would you be talking about Jermaine95? He's done that to me several times as well. He manages to quit in such a way that we
both get a loss it seems. Had the same thing happen to me in Tekken 6 and Tekken Tag Tournament 2, players who were on wireless and swiveled their antenna in such a way to disrupt the connection long enough for the game to not register it as intentional, but instead a network error