Kildare middlemen bringing horse over for Irish writer (6)
I believe the answer is:
keegan
'irish writer' is the definition.
The definition suggests a singular noun which matches the answer.
'kildare middlemen bringing horse over' is the wordplay.
'kildare middlemen' becomes 'kee' (I can't justify this - if you can you should give a lot more credence to this answer).
'bringing' is a charade indicator (letters next to each other).
'horse' becomes 'nag' (term for an old horse).
'over' is a reversal indicator.
'nag' reversed gives 'gan'.
'kee'+'gan'='KEEGAN'
'for' acts as a link.
Can you help me to learn more?
(Other definitions for keegan that I've seen before include "Kevin --, footballer" , "Former footballer" .)