I salute you for opening this thread up. I shows you have so much interests in football to the point that you researching to encounter the problem.

I don't have much to say, but i think it is not only you who having this problem but world class team too as i see they are struggling too.

The main things you need to be aware is the how is the whole team's effort in defending, you can't do all defending by yourself. World class team's player always tracking back the opponent during opponents attacking not only the defenders but even the strikers.

It's all about team work mate, football is about team work. I hope it helps.