beat the pants off vs fisticuff

beat the pants off

verb

  • To thoroughly and decisively defeat someone, either in a physical fight or, figuratively, in a competition. 

fisticuff

verb

  • To engage in a physical fight. 

noun

  • A fistfight. 

How often have the words beat the pants off and fisticuff occurred in a corpus of books? (source: Google Ngram Viewer )