Eager to have a shot at goal, initially (4)
I believe the answer is:
agog
'eager' is the definition.
(I've seen this before)
'a shot at goal initially' is the wordplay.
'shot' becomes 'go' (both can mean an attempt).
'at' is a charade indicator (letters next to each other).
'initially' suggests taking the first letters.
The initial letter of 'goal' is 'g'.
'a'+'go'+'g'='AGOG'
'to have' acts as a link.
(Other definitions for agog that I've seen before include "Expectant and wide-eyed" , "Enthusiastic" , "Looking amazed" , "In a highly excited state" , "Open-mouthed" .)