banjo hitter
noun
baseball
: a batter who lacks power : a weak hitter
The public address system announces each batter with thundering resonance, whether it be Babe Ruth or a banjo hitter just called up from Vancouver.
Martin F. Nolan, Boston Globe, 12 Aug. 1998
Martin F. Nolan, Boston Globe, 12 Aug. 1998 banjo-hitting adjective
… I was a scrawny, banjo-hitting second-baseman. King Kaufman, Salon.com, 7 Jan. 2009
King Kaufman, Salon.com, 7 Jan. 2009 
Word History
Etymology
banjo hit "a weakly hit ball" (from a fanciful comparison of the pinging sound made by a weak hit to the sound of a banjo) + -er entry 2
First Known Use
1935, in the meaning defined above