Chairman Nigel Wray said: "We'd all like to thank Mark for his dedication and commitment over the past six years and wish him all the best as he seeks a fresh challenge."

"Throughout those six years, Mark has worked really hard on the structures within the club and we are now beginning to see the benefits of that both on and off the pitch. On behalf of the Board of Directors, we would like to thank him for all his efforts.

"However, I'm delighted to say that Mark is not leaving us completely as we will be able to continue to use his knowledge and experience, as he is remaining a consultant with the club."

Mark explained that he felt the time was right to move on to a new challenge.

"I've had six fantastic years at Saracens and I'm very proud of what we have been able to achieve during that time," he explained.

"When I first joined the club, the challenge was to put in place structures across the board to make us a better rugby club.

"We have a world class coaching set-up and an Academy that is ranked as one of the best in the country and is producing great results.

"We haven't been able to turn that into trophies as yet, but hopefully that's not too far away and I believe the club is now at the point where we will be consistently competing for honours.

"I am happy the club is in a much better position than when I started, but I feel that the time is right to move on to a fresh challenge.

"On a personal level, I would like to thank Nigel and the Board for the support they have given me.

"As a family we have had a fantastic time and we have no immediate intention to return to Australia, but some of the projects that I'm working on could see me visit."

"I'd also like to thank all the staff, coaches and players at Saracens for their efforts and the wider rugby community for their support over the years."

Edward Griffiths, current CEO of Saracens umbrella company Premier Team Holdings, has been given the role at Saracens.

Wray explained: "Edward has huge experience within rugby having been CEO of South African Rugby during their World Cup win in 1995 and more recently on the country's bid for the 2011 World Cup.

"Edward has been working within Premier Team Holdings for the past six months and we're looking forward to him continuing to build and develop on the structures that Mark has put in place."