left field vs left-winger

left field

noun
  • The defensive position in the outfield to the left. 

  • An unusual or unexpected position, or a viewpoint held by very few others in contrast to the majority viewpoint (especially in the phrases out in left field and way out in left field) 

  • An unexpected, bizarre, or unwatched source (especially in the phrases out of left field and from left field). 

  • The part of a baseball field which is beyond the infield and to the left of a person standing on home plate and facing the pitcher. 

left-winger

noun
  • A person who plays the position of left wing. 

  • A person who espouses left-wing political views. 

  • A member of the left wing of a party or group. 

How often have the words left field and left-winger occurred in a corpus of books? (source: Google Ngram Viewer )