A blessing, finally, in the long run (5)
I believe the answer is:
grace
'a blessing' is the definition.
(synonyms)
'finally in the long run' is the wordplay.
I cannot really understand how this works, but
'run' could be 'race' (synonyms) and 'race' is located in the answer.
A single letter 'g' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for grace that I've seen before include "'Amazing - - '" , "Elegance of movement" , "kindness" , "Easy elegance" , "Famous cricketer" .)