No more than minutes before (4)
I believe the answer is:
mere
'no more than' is the definition.
(I've seen this before)
'minutes before' is the wordplay.
'minutes' becomes 'm'.
'before' becomes 'ere' (usually literary).
'm'+'ere'='MERE'
(Other definitions for mere that I've seen before include "bathing may be permitted in this?" , "Simply, nothing more than" , "Former lake" , "Lake (poetic); Maori war club" , "a drop of water" .)