I had a match in CL with a guy that had like 3% less than me. I was playing away. Minute 10 I lead by 1-0. In the next minutes this guys has 6 fans spectating giving him a boost of 12%. He beats me 4-1. I don't mind loosing, even if I take care of my team and invest time in this game, I understand there will always be better managers, but to lose because a guy calls his friends to watch his game is bad. I talked to support. They said that this can happen, it's permited and they have a limit of the bonus...15%. 15! Just to understand, when you watch your team and you get that 8%, it is clear that it helps you. My team always performs better when I spectate the game. Imagine how much 12 or 15 %, affects the outcome. So I can have a well trained team, with superb morale, 90%+ rest and still lose to a lesser team, because my oponent called his friends to help him. I'm only in my 4th season, but already thinking to give up this game. Besides this issue, bad updates and a constant pressure from the developers to spend money, I'm getting tired. My advice for people who plan to spend money on this game: don't! You will only get frustrated when you will be treated unfair.
Oh, also the players get tired quicker and lose morale quicker that in the previous season. Developers should take care of those issues if they care about their users.