Anger as sacked without protection (3)
I believe the answer is:
ire
'anger' is the definition.
(ire is intense rage)
'sacked without protection' is the wordplay.
'sacked' becomes 'fired' (both can mean dismissed from a job).
'without protection' means to look at the middle letters (no outside letters).
The middle letters of 'fired' are 'IRE'.
'as' acts as a link.
(Other definitions for ire that I've seen before include "Choler" , "Losing head" , "'Anger, wrath (3)'" , "Anger among admirers" , "exasperation" .)