It's scripting - I hope they get it out of the game for next year.
For example, career mode offline. Up to today, I had 7 league wins and 1 draw on legendary(the one draw was Chelsea(a) 3-3 when the ref played about 20 minutes of added time despite the ball going out about 4 times in that time.)
I then played Celtic in the CL, just as I have on two previous occasions. In the previous 8 games of my league season, I'd conceded 5 goals. I proceeded to lose to Celtic 9-1, with my defence going completely insane every time they had the ball. They scored with every shot, and scored 4 times from corners that they got from my players randomly misplacing passes off the pitch and running into each other. I knew what to expect though - Scottish teams are unplayable away from home - my two previous games with different teams had ended 8-3 and 7-1.
I turned to the online modes, and proceeded to win about 8 games in a row, and then I needed a solitary point to gain promotion. I then was struck down by the scripting, and I lost 8-2 to some randomer who actually sent me a message saying that he was sorry that the game was so fixed, unbelievably.
I'm not one of these types to moan about things, but this is literally the most ridiculous game I've ever played. I find myself playing it just so I can prove it's fixed. In certain games, keeping a clean sheet is physically impossible. I played the same individual match in career mode six times(Roma v Cagliari, surely a simple enough home win) and was 3-0 down at home after 10 minutes on each occasion. I often concede a goal in the exact same minute of the game if I quit and start again. The other week Torres scored in the 11th minute in 4 consecutive games.
FIFA came up with this plan of making it harder to win offline, which was fine, because it was basically far too easy to slaughter United about 8-0 on legendary. The problem is now, however, that they haven't made it harder to win in terms of actual gameplay, but they just script it so you lose certain games or concede goals at particular times. If you're a player that actually just wants to play the game honestly, you're stuffed. It's just hilariously unrealistic. Jay Spearing scored a hat-trick against me the other day because I had the nerve to man-mark Suarez. Needless to say, the computer let me score in the second half so I won 4-3. Rubbish.
I put it down to world class, just to see what would happen, and I established that it was just the legendary of FIFA 11. Far too easy. 4-0 every game.
What's most ridiculous is how they deny the scripting on any of their official forums. Type in 'fifa scripting' to google and there's millions of people saying the exact same thing as I am, with some EA representatives saying that it's just their poor play. Bollocks.