A one-man club? (4)

I believe the answer is:

iron

'club?' is the definition.
(type of golf club)

'a one-man' is the wordplay.
'a one' becomes 'I' (Roman numeral).
'man' becomes 'ron' (short for Ronald).
'i'+'ron'='IRON'

(Other definitions for iron that I've seen before include "Flatten; element" , "Press - element" , "Main part of steel" , "stern" , "Smoother - metal" .)

I've seen this clue in the Evening Standard.

Want a hint initially instead of a full solution? Install my app