Hard throw, in baseball (3)
I believe the answer is:
peg
'hard throw in baseball' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for peg that I've seen before include "Clip for attaching clothes to line" , "Clip for hanging washing" , "Fix (a price)" , "Brandy and soda drink measure" , "Hook" .)