Outside Runs

Question
Hello Coach!
I'm having some trouble on coaching this point in my Defense. We are in a 4-3 Base and the opponents are always getting huge yardage when running to the outside (like an off tackle play). First I tried to have my DE (responsible for C gaps) with a wider split (like 4ft away from the OT) but still if the OT can get a hand on them or if the RB can get a wider angle they can't pursue and tackle the RB (my DE are strong and have good technique on pass rush but they are too slow to pursuit a RB running outside of them). They also say that the pass rush is slowed down if the are on wider splits.
My second try was to put our OLB on a wider allignment and have them help on the outside pursuit but then we became too vulnerable with runs on the B gaps as the OL get better blocking angles on the OLB pushing them towards the sideline.
Do you have any idea on what can I do about this?
Thank you very much!

Answer
Hello.

It is about reading your keys, gap responsibility and gap filling. the defensive end is not squeezing enough and the linebackers are not flowing and filling gaps fast enough. Also your safeties are key in these type runs. Example: Out of the I formation. The "O" end blocks your "D" End, the tackle is either blocking down on the D tackle or gets the Sam linebacker,the guard wither blocks the D tackle or G's and gets the Sam linebacker. The center tries to get the Mike linebacker before he fills, if not the lead back gets him, the center catches the willie linebacker scraping. The only person left to fill that game is safety. So if the defensive in can squeeze without giving up the outside...Everything should be covered...