Thrust upon
Definition 1 of 1
Pro Tip 1/3Unexpected Responsibility
Refers to sudden responsibilities or roles that someone must take on without being prepared. 
After the CEO's resignation, the responsibility of leading the company was thrust upon his young protege.
Pro Tip 2/3Negative Surprise
Often implies an unwelcome or unpleasant surprise, not necessarily a physical action. 
She found the task of organizing the entire event thrust upon her at the last minute.
Pro Tip 3/3Lack of Choice
Highlights the absence of choice for the person having to accept the situation or task. 
With no one else qualified, the duty of training new recruits was thrust upon him.