Pitcher's pitch (6)
I believe the answer is:
slider
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">pitcher's pitch</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for slider that I've seen before include "Control knob move up and down or sideways" , "Control such as on a mixing desk" , "American snack" , "Eg, fader control" , "Sir led (anag) - control mechanism" .)