Petrillo's long-standing relationship with Adelaide United has come to an end, resigning from the club he helped to establish back in 2005.
“It was a very difficult decision for me to make, but after ten years I thought it was the right time to make the change now before the start of the new season to allow a period of transition,” he said.
Director of Adelaide United, Bruno Marveggio, said Petrillo’s decision took everyone by surprise.
“The decision comes as a complete shock to everyone associated with the Club,” Marveggio said.
“We respect Michael's decision and are very thankful for everything he has done for the Adelaide United Football Club.
In 2007, Petrillo departed Adelaide to help establish the North Queensland Fury Football Club, before returning to the Reds less as director of football less than six months later.
“I’m so thankful to have been able to work for a great club and leave with some fantastic memories and life-long friends. The club is primed to move forward with a great coaching and playing group and an amazing training facility now in place” he said.
Over recent years, Petrillo has overseen the implementation of a new football philosophy into the Club, which is now widely acknowledged as the most entertaining style of play in the Hyundai A-League.
He was also instrumental in the development of Adelaide United’s new state-of-the-art training facility at Playford and the successful introduction of the club into the FFSA National Premier League.
Petrillo will continue in his role until 30 September 2015 and will assist in finding a replacement for the position he will leave vacant.
