I was playing a 2v2 rated game with a clan mate, once we started to enter the game there was only one player, obviously i thought this was strange. As soon as the game started my ally said to me he recognized the name as a prolific cheater. Obviously we were winning then he resigned we said gg and went back. Our ratings hadn't changed one bit, we knew what was to come. Minutes later our scores were lower and his was higher.
Sounds like the same thing which happened to you.
Computer games don't affect kids; I mean if Pac-Man affected us as kids, we'd all be running around in darkened rooms, munching magic pills and listening to repetitive electronic music. - Kristian Wilson, Nintendo, Inc, 1989