Logic in Physics in Writing an Action Scene

Good morning fellow writers and aspiring ones.  Hope you have a great start to your day.  I have a very bad cold, but my mind is still on the story in my congested state.


I do have an inquiry and appreciate your input.  If you are a horse rider, this maybe your expertise.  
In my story I have a rider that gets jumped on by an assailant.   There are several options to this scene.  Do you recall Indiana Jones jumping on a guy on a horse?  That horse curled in and fell, but got back up again.  It's almost like that.

If my character in my story is an experienced rider, gets jumped and the horse maintains its balance, then all the better in this scenario.   IF the man jumping on my character is meant to kill the character, jumps on the man on the horse, what is the best way to outmaneuver this to survive?


Again I appreciate all your input.  Action scenes are tough when logic, strength and physics of an attack is the focus of the story.   Harrison Ford is a good horseman by the way.


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