Resentful as sarcastic remark interrupts pub worker (9)
I believe the answer is:
indignant
'resentful' is the definition.
(thesaurus)
'sarcastic remark interrupts pub worker' is the wordplay.
'sarcastic remark' becomes 'dig' (dig can mean a hurtful comment).
'interrupts' is an insertion indicator.
'pub' becomes 'inn' (an inn is a type of pub).
'worker' becomes 'ant' (worker is a type of ant).
'dig' placed into 'inn' is 'indign'.
'indign'+'ant'='INDIGNANT'
'as' acts as a link.
(Other definitions for indignant that I've seen before include "not happy" , "Annoyed at unfair treatment" , "Miffed" , "Angered by unjust treatment" , "Anger at having been treated unjustly" .)