Port Adelaide will ban for life the supporter who threw an object at Adelaide forward Eddie Betts late in Saturday night’s Showdown if it is found her act was racially motivated.
Power chairman David Koch announced the penalty on Sunday afternoon.
Her club membership for next season has been revoked immediately.
The incident occurred in the final quarter of Adelaide’s 15-point win over the Power.
Both the Crows and the Power released statements in the early hours of Sunday morning condemning the behavior.