The appointment of a new chair of the Melbourne Market Authority board may have been the catalyst for an almighty upheaval of the board. width=device-width, initial-scale=1, shrink-to-fit=no" name="viewport"/>Market board members quit after former Demons boss Paul Guerra takes top job. The Carroll government’s appointment of sacked Demons boss Paul Guerra to the chair of the Melbourne Market Authority (MMA) has led to a dramatic resignation of its board.