Boasted of oarspeople (4)
I believe the answer is:
crew
I believe this clue is a double definition.
'boasted' is the first definition.
('crew' is past tense of 'crow', meaning to boast)
'oarspeople' is the second definition.
(crew of a rowing boat)
'of' acts as a link.
(Other definitions for crew that I've seen before include "They operate ships or aircraft, say" , "Ship's operators" , "Provided a wake-up call" , "Group of operators" , "eight > was sounding shrilly" .)