Premiership-winning coach Gary Van Egmond has quit A-League club Newcastle to join the Australian Institute of Sport (AIS).
Van Egmond, who steered the Jets to victory in the 2008 A-League grand final, told the club on Sunday he was leaving immediately to become head coach of the AIS' football program.
Jets chief executive John Tsatsimas says a search to replace the 2007-08 A-League coach of the year will begin by the middle of the week.
"We're digesting everything that's transpired and we'll internally work out a way forward in terms from where we stand at the moment and hopefully something will be announced in the next few days," Tsatsimas told AAP.
Van Egmond's departure ends one of the most successful coaching tenures in A-League history, with the 43-year-old taking over the Jets' hotseat in round seven of the 2006-07 campaign.
At that point the Jets were winless and last on the ladder but Van Egmond steered the club to the finals.
The following season Van Egmond guided the club to second on the ladder before beating the Central Coast Mariners in the grand final to deliver the club the A-League title.
Van Egmond had guided the club to the last 16 of this year's Asian Champions League but his last game in charge was a 6-0 thrashing by Korean club Pohang Steelers to end their interest in that competition.
The Jets begin this year's A-League season on August 9 and while Tsatsimas conceded searching for a new coach so close to the season start wasn't ideal, he felt the club would be ready when the kick-off does come.
"No it isn't, but having said that these are the circumstances that we have to deal with," he said.
"We're moving ahead with it now and hopefully we'll be in a position to start matchday one in a prime position."
Jets technical director, and former Sydney FC coach, Branko Culina has been reported as the favourite to take over from Van Egmond, at least in the short term.
Van Egmond was unavailable for comment.