Help Protecting Leads

[KunAndFriends]

I lost on an 89th minute goal in my semi final cup match against a slightly better team. (38.2v36.6) In the first match I joined halfway through with a 2-0 lead, only to watch my team give up two goals despite the possession boost. In the first match, I switched from a 3n-1dm-4-2 to a 5-2dm-2w-1 without switching any team instructions, but allowed two goals. (Attack:normal-mixed-mixed-off Defending:Low-normal-zonal-offside trap off) In the second game, I started with the same formation/instructions and it was tied 1-1 in the 75th minute with the lead on away goals. I then switched to a 4-1-4-1 and switched my mentality to hard defending without switching anything else. My question is what is the best way to protect the lead? My team is well rounded so the subs I bring on aren't really a drop off in quality. I'm not using high pressing or man marking to drain stamina either. Is this just bad luck or is it best to defend using possession instead of reinforcing the back?

[nikolgiorgos]

4 def. +1 DMC are enough for me to keep the lead (unless oppo has 3ST + AMR+AML).
Mentality defense of course, no offside, yes to counter and better man-to-man if Q equal or better (I know about stamina but for critical games like semi final it's worthy to spend some extra greens).
Also blue arrows on defenders.

[El Pistolero]

I believe you changed to many positions.

I would of subbed a striker to put in a full back and swapped a CB to the other fullback position so it was 4-1-4-1.

[KunAndFriends]

4 def. +1 DMC are enough for me to keep the lead (unless oppo has 3ST + AMR+AML).
Mentality defense of course, no offside, yes to counter and better man-to-man if Q equal or better (I know about stamina but for critical games like semi final it's worthy to spend some extra greens).
Also blue arrows on defenders.

I usually blue arrow my DM. Wasn't sure if blue arrows for defenders makes them more passive (as in look to make more interceptions than playing tight to their man) or to focus more on defending. I'll try using it on my defenders next time. I have a CL semi tonight against a similar ranked team (me:35.4v37.5). I'm only in my third full season at level 3 so I'm still learning some of the ropes. I guess the CL and cups aren't the same level as leagues? My manager history says I finished 3rd in a level 7 cup so I was probably punching above my weight to begin with. My basic strategy has been buying young players (24 is my oldest, with the rest 20 and below) and improving facilities when I have the money. Also buying players at like 2am when there aren't as many people to bid against.