The arrows only serve for a player to advance a little further from his position, then you need not put blue arrows on defense players because it does not retreated more than the edge of the field. Ie no need to use red arrows in ST's (Attackers) nor blue arrows in DR's DC's and DL's.
What about the red arrow on your DMC, I would use the blue because then he would play the role of DMC and DC adiversária if the team has one training with plenty of attack. I hope I've been informative to you.
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