Longing to get first hole in one (4)
I believe the answer is:
Here is my best explanation:
'longing' is the definition.
'first hole in one' is the subsidiary indication.
'first' indicates taking the first letters.
'in' indicates putting letters inside.
'one' becomes 'ace' ('ace' can be a synonym of 'one').
The first letter of 'hole' is 'h'.
'h' placed inside 'ace' is 'ache'.
'to get' is the link.
(Other definitions for ache that I've seen before include "Pain; long (for)", "strong feeling", "Feel pain", "A dull lingering pain", "Persistent dull pain", "Dull steady pain", "Steady pain", "suffer", "Nagging pain" and "Cause pain".)