After a goalless first half Ross Stewart scored twice after the interval following two crosses from Jack Clarke.
Clarke then got on the scoresheet after an excellent run and finish, before he was substituted to a standing ovation.
The result means Sunderland have taken 11 points from their first seven league games this season.
Our chief Sunderland writer Phil Smith has dished out his player ratings from the Stadium of Light:
13. Hemir (sub) - 6
Almost turned his first touches into a goal, crashing an effort just wide of the post. Ran well to help his side out. 6 Photo: Frank Reid
14. Lynden Gooch (sub) - 6
Brought a burst of energy late on to help see it out. 6 Photo: Frank Reid
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