A safe bet - Idioms by The Free Dictionary
a safe bet
a safe bet (British, American & Australian) also a sure bet (American)
1. something that you are certain will happen It's a safe bet that those two will settle down and have children. Wheeler is a sure bet for a place on the team.
2. someone or something that you are certain will win or succeed She is still a safe bet for re-election. Simplicity of design is a sure bet in the fashion world.
References in periodicals archive
They probably heard the final score from Visalia, but it's a safe bet
the JetHawks were unaware how the Modesto A's had lost.
It's also a safe bet
to say the current crop of A's would not have as good a record if La Russa, who often made it difficult for inexperienced players, had stayed.