bush league vs duffer

bush league

noun
  • A professional sports association at the lower levels of minor league organization. 

  • A low-ranking or inferior level among groups, professions, organizations, etc. 

adj
  • Of inferior quality. 

  • Amateurish, unprofessional, unpolished, juvenile. 

duffer

noun
  • A player having little skill, especially a golfer who duffs. 

  • An incompetent, indolent, or clumsy person. 

  • Any of various nymphalid butterflies of the genus Discophora. 

  • A racing pigeon that does not perform well. 

  • A cow that does not produce milk. 

How often have the words bush league and duffer occurred in a corpus of books? (source: Google Ngram Viewer )