Some patterns about possible fixed leagues is that I had a lot of leagues where I will face the numbers 2,3, 4 and 5 in the last 5 games of the league. Mostly the number 2 in the forelast game.
I had a season where I had a very bad start with loosing 4 out of 5 games against all odds (had by far the highest quality). I was almost ready to tank that season. As the season progressed I started to get a lot of players in the top 5 ratings. In the end the second half of the season were 12 wins and 1 tie and I won the league anyway.
I do have the feeling there are some fixed results. I have made subs for players that were dropping in ratings like mad. Made the sub and had to wait 12 minutes and still no sub but then the player got a straight red and was out of the game before the sub. A few days back I had a defender who was also dropping in ratings so I swtiched him out. The new player went from 6,5 to 5,1 in 3 minutes and got his first yellow. 5 minutes later he is at 4,5 and he gets the second yellow. So two yellows in 8 minutes.