Needling (8)
(Other definitions for rankling that I've seen before include "causing resentment" , "annoying" , "Grating, irritating" , "Causing endless annoyance" , "getting up one's nose" .)
(Another definition for provoking that I've seen is " Stimulating (a reaction)".)
'needling' is the definition.
('goad' can be a synonym of 'needle')
This is all the clue.