Open nothing up for him (8)
I believe the answer is:
franklin
'him' is the definition.
'open nothing up' is the wordplay.
'open' becomes 'frank' (synonyms).
'nothing' becomes 'nil' (eg nil is zero in football).
'up' says the letters should be written in reverse (in down clue: letters go upwards).
'nil' written backwards gives 'lin'.
'frank'+'lin'='FRANKLIN'
'for' is the link.
(Other definitions for franklin that I've seen before include "Tale-bearer" , "One with a tale to tell" , "Benjamin or Roosevelt" , "[PILGRIM in the CANTERBURY TALES]" , "Statesman" .)