with the gloves off
With or ready to dispense rough treatment, as in Prepared to oppose the council, the mayor marched into the meeting with the gloves off. This idiom alludes to old-style boxing, when gloves were not used. [Early 1800s]
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.