Position of US player in two garments (9)
I believe the answer is:
shortstop
'position of us player' is the definition.
'shortstop' can be an answer for 'player' (I've seen this before). I'm unsure of the 'position of us' bit.
'two garments' is the wordplay.
'two garments' can mean two substitutions for 'garment'.
'garment' becomes 'shorts' (shorts is a kind of garment).
'garment' becomes 'top'.
'shorts'+'top'='SHORTSTOP'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for shortstop that I've seen before include "US player" , "Fielder in baseball" , "position in American sport" , "Opening move" , "One in field" .)