To add the my previous post, you decided that Counter (which is already fairly deep) needed to be deeper.
You decided the both fullbacks needed to be on Defend, which causes them to stay back, behind play. How did this affect build-up play?
You also decided to mark Hazard tight and to dive into tackles that your defenders aren't all that sure they'll win, against a quick-footed, two-footed player. This raises a million questions. With the fullbacks now deep and in line with the D-line, were they tight on Hazard often or was he able to drop deeper into space? When he did get the ball, was your tackling instruction working? Did you at any point look to see if it was? Did you change anything if it wasn't working?
You decided to close down Costa. Same questions. Did you at any point look at the closing down of Costa to see if this change to your system worked as planned? Why wasn't it working? Was he able to find space too easily? Where was this space? Was he able to just dribble past your defenders? etc.
1.I watched both games on comprenhave, the second leg almost all game on full match actually because I couldn't believe what I am seeing.
2.I put the fullbacks on defend after 30 minutes or so because Hazard was every time played over my fullback with a deep pass, and cross freely.After that this kinda stop, but he could still beat my man easily and put crosses in.
3.Yes, I decided to mark Hazard tight and tackle him hard but this didn't show at all in the game.When he got the ball was free, no one was tight marking him.And no one tried to tackle him honestly.
4.Costa scored a hattrick only with headers if I remember correctly, second goal from a corner.He was never closed down, I mean they were FREE headers in the box, none of my defenders were near him.
Now, in the 2nd leg I don't know what happened.I started with attacking, push higher up, more direct passing, get stuck in and exploit the flanks if I remember correctly and I just played them off the park.
This is my biggest comeback ever in Football Manager.After I went 4-0 up I decided to go defensive and I defended with the same instructions that failed miserably in the first leg. I mean, counter and so on, that's why Chelsea had more shots than me, but honesty, they never looked like scoring, my team defended very well, Chelsea didn't create anything important.I also changed to shorter passing and retain possesion.My fullbacks were on defend too.
After 80 minutes or so I went defensive, changed the tactic, put both of my CMs to DMs with a defensive midfielder and a ball winning midfielder role and also moved the AMC to MC and set him as DLP.
So, I don't know what to take from this, maybe the problem really is in the away games.