Base to base contact with enemy and not in combat

[jonno]

Hi

This may be one of those things that can happen... but

At the start of my turn - I had a unit of Medium infantry in base to base contact with a unit of cavalry. Both units were facing towards each other. It was only after I charged with a third unit and the cavalry evaded that I realised there was no "arrow" indicating combat.

Sorry I can't remember how the units got to this position.

I am wondering if there is a reason for this under the game system. And also if had I attacked with the unit in contact would the cavalry still been able to evade - i assume so.

thanks, Jon