To arrange golf in African port is ultimately inane (8)
I believe the answer is:
organise
'to arrange' is the definition.
(organising is a kind of arranging)
'golf in african port is ultimately inane' is the wordplay.
'golf' becomes 'g' (phonetic alphabet: alpha, bravo, charlie etc.).
'in' is an insertion indicator.
'african port' becomes 'oran' (I've seen this before).
'ultimately' suggests the final letters.
The last letter of 'inane' is 'e'.
'g' going within 'oran' is 'organ'.
'organ'+'is'+'e'='ORGANISE'
(Other definitions for organise that I've seen before include "Classify - Iron Ages (anag)" , "form" , "Devise and direct" , "run" , "Onagers I manage to make arrangements for" .)