David Gallop is stepping down from his job as chief executive of the Australian Rugby League Commission immediately.
NRL club bosses have reacted with shock and surprise to the sudden resignation of the game's longtime chief executive David Gallop.
Four months into a four-year deal with the Australian Rugby League Commission, formed in February to take over running the code, Gallop departed by what was described as "mutual agreement" on Tuesday.
Gallop enjoyed strong support of the clubs throughout his 10-year reign as NRL chief executive and the news he was stepping down from his high-profile role blindsided many of his fellow administrators.
Gallop was gracious in his parting words in a joint statement with ARLC chairman John Grant.
"It's been a privilege for me to lead the game over the last 10 years and see the game's resurgence," Gallop said.
"I love the game and wish it well. I would like to thank the clubs, the players, my staff and the fans of the game. It has been an exhilarating and challenging period, but no one can do this job forever."
Grant said Gallop understood the need for a fresh approach under the new ARLC administration.
"Taking this into account and with the interests of the game at heart, the board and David have reached an agreement that the game needs a different style of leadership detached from the past for the next stage of its development," Grant said.
Grant added the search for a new CEO would begin immediately with NRL general manager of strategy Shane Mattiske to take over the leadership in the interim.
Sydney Roosters chief executive Steve Noyce was taken aback at the news.
"I was shocked to be honest," Noyce told AAP.
"I was genuinely shocked and I think most people in the game are.
"I was one of David Gallop's biggest fans. It is a really, really tough gig and I think even his biggest detractors will admit he gave it 100 per cent.
"When you look at everything he had to deal with, he did his job in a decent, honest and transparent manner. He is a wonderful administrator and leaves our great game in a very healthy state."
Sharks chairman Damian Irvine said Gallop had left rugby league better than when he began in 2002.
"When David took over we had a great game that was under duress, now we have a great game that is no longer under that duress," Irvine said.
"It is surprising news. I think it is a good thing that it has not been played out in the media and dealt with in a very professional manner."
Raiders chief executive Don Furner travelled to Wagga Wagga with Gallop last week on a development trip and said Gallop gave no indication that he was considering stepping aside.
"I am taken aback by it all," Furner said.
"I spent some time with him last week and definitely didn't see this coming.
"David did such a tough job so well. I don't think until you are close to it anyone can understand just how tough a job it is. I thought he would have kept working on the TV deal so it does come as a shock."
"He led the game through some tough times when you think about the salary cap scandals.
"He did a great job in cleaning up the game's image. And I don't think anyone else in any other sport, in AFL or Super 15, would have taken the strong stance that he did on the salary cap scandal."
"He has been a great administrator for our game and I wish him all the best."