Wiktionary
duke it out
vb. 1 To fight, especially with the fists. 2 (context idiomatic English) To argue heavily or at length.
Usage examples of "duke it out".
Let the Nightmare and my godmother duke it out for who gets to be first in line.
Anthony was sitting there grinning, delighting in watching the elders duke it out verbally.
Who wants to duke it out with a dead Loghyr who's had several thousand years to practice being nasty?
The Freelies and Imperials duke it out, allowing the Rebels to escape.
Instead he was keeping everyone on the move, wearing them out, not looking for a good place to rest up, prepare a major ambush, duke it out, and then take off again.