How to Auto-Reject Approval if Position is Blank

Summary

Is there a way to auto-reject an approval if the position field is left blank?

Content

I have a scenario where I want the approval to auto-reject (I know how to do that part) if the position is blank and two other criteria are met. 

Under List is a List, I have the following criteria.  When I inactivated all the other rules to test just this one and submitted a promotion on an employee, the approval failed. I've tried with Position and Position Code.  I know it has to do with the position logic because in another rule I have where the position isn't null, and the task routed for line manager approval even if the position was blank.