duke it out

US /duːk ɪt aʊt/
UK /duːk ɪt aʊt/
"duke it out" picture
1.

一決高下, 打一架

to fight or compete to resolve a dispute or determine a winner

:
The two rivals decided to duke it out in the final round.
兩位對手決定在最後一輪一決高下
Let's just duke it out and see who's right.
我們來一決勝負,看看誰是對的。