Look to maintain rise (4)
I believe the answer is:
peek
'look' is the definition.
(peek can mean to look at quickly)
'maintain rise' is the wordplay.
'maintain' becomes 'keep' (synonyms).
'rise' says the letters should be written backwards.
'keep' back-to-front is 'PEEK'.
'to' acts as a link.
(Other definitions for peek that I've seen before include "Sly look, peep" , "spy" , "Furtive glance" , "Secret look" , "Repeatedly look like this" .)