Last 5 games ratings

Do the last five games ratings on a player's profile only count for the competition that comes next? I have a midfielder that I usually use as a back-up, but as my first choice was injured, I used him. He started to play well for my Ajax side but, when the Champions League game came, my first choice came back and I put him into the team. But before this game I saw my back-up midfielder with - what I believe to be - a lower rating than I think he had. I do not follow them to often, that is why I can't recall what rating he had before the UCL game.