Cant seem to stop the RUN

[teampunjabi]

Me and my brother play All - Pro with RB ability at 55 and USER and CPU tackling at 40. This was done to limit fumbles. But I cant seem to stop the run. He does Singleback and Iform and just runs up the middle EVERY time. I do shifts for both Dline and LB's to the middle. It seems like when you do this theres almost TOO many people at the line and he squeezes through while he gets tackled from behind and falls forward for 5- 6 yards every time. Do you think its the sliders??? Or am I doing something wrong?

[Rules]

Go with some goalline up the gut blitzes and shadow his running back. Mix it up and bring the front line in tighter just before he snaps the ball.