Can't tackle, won't tackle.

[red dragon1978]

Playing as Wrexham, League 2. I'm using a 4-1-2-3 DM Wide for away matches, on the counter and direct. At home, I use a 4-2-4 short passing control system.

In both, I use fullbacks.....supporting away, automatic at home. Narrow sitting IF's and a Target Man or Advanced forward on Attack (with a DLF at home) A defend duty BWM, a support duty B2B, and away, a defend duty defensive midfielder instead of the DLF

And I just can't get any of them to tackle. I'm playing Crewe right now....I paused the game to type this after the sixth incident (in the first 13 minutes) of watching one of my players (both fullbacks, the BWM, and one of the IF's) track the run of an opponent, running beside them and doing precisely nothing until they pass. I'm using Get Stuck In and Tight Marking team instructions, I have the BWM and DM with 'Get Stuck in' PI's, and I've told my IF's and AF to close down much more, and my IF's to get stuck in (thought asking the same of my AF would cause him to lose some of his attacking effectiveness, plus conceding free kicks and therefore possession). And, simply, they aren't. What've I missed/got wrong?

Crewe are playing a variation of 5-3-2 it seems, with the wing backs pushed far forward to create a 3-4-3, 3-4-1-2, or 3-5-2 depending on the behaviour of their AM...in their previous game he dropped into midfield to create a three, but they're using a different man and I haven't figured him out yet. Obviously, this leaves massive gaps behind the wingbacks, so I'm aggressively targeting the wings, focusing down them and clearing to wings, to try and get the ball into that area. However they are very quick, very organised and like to switch flanks and move the ball quickly. Therefore I want my more defensive midfielders getting into them to try and disrupt their build up, and my attackers to get into the defenders to help the ball stick up top. And they're just not doing it. Thoughts please! And thanks