League Random results

[WalkingPenguin]

I know I have a good side. Am in Platinum association and win 8 out of 8 this season.
Am in the semi finals of the cup and just beat a team 18% higher than me to reach quarter finals of champions League.
But my league form is awful. Lost 8 out if 14 and am 9th in the league, despite playing the same eleven players. They go from a 9 rating in a cup or association match to a 6 rating in a league match.
Is there a random variable in the game that differs between, league, cups and association matches.
How can the same side go from brilliant to rubbish in the space of 2 games?

Give it up, just play it, its not your mistake or your tactic, like me, beaten by some team, then next match against him, i won, thats it. unless you have big advantage like having 40% up team, you cant predict the game.