It emerged last month that the former coach, who took over the hotseat in the immediate aftermath of Roy Keane's departure and kept the club in the Barclays Premier League, was to end his spell on Wearside.
However, Quinn has now confirmed that he has left his role as chief scout, to which he was appointed in the wake of Steve Bruce's arrival, by mutual consent.
Walking away: Ricky Sbragia has left Sunderland two years after he was axed as the club's manager
The chairman told the club's official website: 'Ricky has been a tremendous servant to our club - firstly in a coaching capacity, then of course taking the helm after the departure of Roy Keane and latterly as chief scout.
'Ricky is a true footballing man and we will always be grateful to him for everything he has done for the club. We wish him all the best for the future.'
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