Tight race to pocket gold (4)
I believe the answer is:
taut
'tight' is the definition.
(I've seen this before)
'race to pocket gold' is the wordplay.
'race' becomes 'tt'.
'to pocket' is an insertion indicator.
'gold' becomes 'au' (Au is the chemical symbol for gold**).
'tt' going around 'au' is 'TAUT'.
(Other definitions for taut that I've seen before include "Held in tension" , "Fully stretched" , "Without slack" , "Tense, stretched tight" , "Pulled or drawn tight" .)