Definitive Illegal Formation Rules

[VincentAdams117]

So I have been really good in my first season and currently in my second. But my DR got hurt. I put together a formation of :
GK
DC DC DC
DMC
MC MC MC

ST ST ST
IS this formation not valid and that is why I have done really bad my last two matches?

[whiterabbit]

So I have been really good in my first season and currently in my second. But my DR got hurt. I put together a formation of :
GK
DC DC DC
DMC
MC MC MC
ST ST ST
IS this formation not valid and that is why I have done really bad my last two matches?

that is an illegal formation as u have no players on the flanks....u need at least 1 player on each flank be it dr/dmr/mr/ don't really know if amr counts i think not