Day saver (4)
I believe the answer is:
hero
'day saver' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for hero that I've seen before include "Lamp-lighting lover" , "Man admired for outstanding bravery" , "eg Achilles" , "Person renowned for bravery" , "Leander's lover, who committed suicide when he drowned" .)