I don't know how they do it, but the ratings in the game are pretty fair. I usually know when I've played bad and get a 5.5. And the reason is, that the rating is very realistic and like real life you can disagree with the computers opinion.
The first thing you have to forget about is passes made, interceptions, and stats in general. I was too fixed on that at the beginning, sometimes to the point you stop playing good football. If you focus on getting open (not running like crazy around the field), getting your passes right, moving the ball and opening spaces, you'll find you get better ratings at the end even if you don't score or get an assist.
If you do that and play well (that doesn't necessarily mean you get all your passes rigth, and intercept a few... you have to make the game move, dribble safely, get your teammates involved, even if they suck, etc...),their are other things that contribute to a better rating:
1- If your team wins, you have a better chance of getting higher ratting. For example, if you played well and scored, you can get a 7 on a game you didn't win or tied. If you would have won that game, you would have gotten a 7.5 or an 8.
2- Assists usually account for better ratings than goals. But goals are more important if you want to become MVP. Like always this is not a 100% rule, because their are many factors involved.
3- It doesn't matter if you play 5 minute matches or 15 minutes. If you touch the ball twice and score or give an assist, you'll have a good rating. The thing is, that with longer matches you usually get more chances to do that, also you get more chances to make mistakes, so try to calm yourself a bit in longer matches. I played my first two seasons in amateur mode in BAL, and 5 minute matches were more than enough most of the time. If I knew I was going to come of the bench I put 10 minutes instead so I would have more chances to get involved in the game. It payed off: my legend is 21 and a star with ratings in the 90's 80's and 70's. Now I played 10 minute matches in regular mode with him to compensate for the difficulty.
4- Use the speed R1 button wisely. You have to use it just to get an advantage, not to move around the field all the time, cause you lose agility and precision. Try to move normally and give normal passes, and use the burst to move down the flanks or to get to balls before your opponent.
5- You have to get involve. Staying all the time at your position is not going to help you and is not real (is football not chess). But don't get crazy, because your teammates are sensitive to the way you play. If you leave a lot of open spaces in the defense or get to close to your teammates all the time you and them are going to make a lot more mistakes.
6- Use the pass request button with discretion. Even if you don't get the ball, if you hit the Pass Request Button, your teammates get confuse and tend to do the first thing that's on their "mind", not always being the right thing. If your not close to the play and/or are surround by opponents DON'T hit it. Try to get open. If they failed its only because It would be very boring to win all the time. If you are patient you'll find they play much better and you'll win more games, thus getting better ratings.
CONCLUSION: Be patient but play your heart out, get involve, and try to play as you would do in real life. Touch the ball, get open, score.
