@Techboy,
I find defending very hard, my tackling is very on or off, and lately most of the time when I go for a tackle I either miss all together and get burned or commit a foul. With that said, I concede the bulk of my goals on the break with an on rushing Nani, Rooney, Robihno etc coming at me with a series of moves that leave me in the dust. I need to practice my D!
Everyone will have their own way of defending, but in my last twenty games I have found my defensive play working really quite well. Firstly you can never leave yourself open to same number attacks (ie one on one, two on two, three on three) it's a recipe for disaster and the CPU will dice through you more times than not. Secondly, and this works for me but many may argue different, I hardly ever actually tackle. I try and get one of my central midfielders whether it be a normal CM or DMF to trail back behind the ball as an extra layer of protection, and jockey without the need for the jockey button. Mostly it's a slight retreat in keeping with where I believe the player will go.
Constantly bear in mind where you want to usher the ball carrier. For example where Nani has possession and is attacking me, I always try and position myself slightly inside that player and showing him slightly more to the outside. Always look to stifle the player that comes inside, and always encourage the ball carrier on the outside shoulder.
I almost always switch so that I'm the one in control of the player and hardly ever pressure with any button. In this game you just have enough time when jockeying the CPU to cast one eye on the bigger picture, so always look for potential danger areas and be receptive to the one two. If the ball shifts, then switch to the next man and once again slightly show the outside.
You'll never keep clean sheets all the time, but that's real life. Concentration is key and you must always try and not panic, lunging in on this game is a death wish, defence is about patience here.
At least for me anyway