Both comrades sadly out of action (4,2,6)
I believe the answer is:
hors de combat
'out of action' is the definition.
('hors de combat' can be a synonym of 'out of action')
'both comrades sadly' is the wordplay.
'sadly' is an anagram indicator.
'both'+'comrades'='bothcomrades'
'bothcomrades' anagrammed gives 'HORS DE COMBAT'.
(Other definitions for hors de combat that I've seen before include "Out of action due to injury" , "Injured and out of action (French)" , "Disabled, out of the fight" .)