A foregone conclusion
Definition 1 of 1
Pro Tip 1/3Predicted Outcome
Use 'a foregone conclusion' to express that an outcome is predicted and expected by everyone. 
With the star player injured, the team's defeat seems like a foregone conclusion.
Pro Tip 2/3No Surprise
When something happens as expected and without surprise, describe it with 'a foregone conclusion'. 
His resignation was a foregone conclusion after the scandal.
Pro Tip 3/3Dismissing Alternatives
It can imply that alternative outcomes are disregarded because the conclusion seems so obvious. 
Everyone considered her win a foregone conclusion, so the other candidates lost hope.