If Haymaker defence isn't lesson number one you fucked up in teaching your students how to defend themselves from the majority of attacks that aren't sexual. Well apart from stressing running.
Getting up from the ground is number two, running sprints and around the block is number three, positional control number four. In order of priorities.......
Also if your attacker uses any straight punches run like shit you aren't beating him he has likely trained stand up for 2-3 years cause for the first two years people don't punch straight without flaring elbows.
Well that is my opinion at least I could be wrong.