Here PA takes a look at four of the potential candidates who could replace him.
Demetriou, now 43, is familiar to English rugby league fans, having spent virtually his entire playing career on these shores, initially with the defunct Lancashire Lynx but for seven years with Wakefield, where he was made captain. He cut his coaching teeth with Keighley and, after returning to Australia, rose to prominence by steering Northern Pride to Queensland Cup glory. That earned him a stint as Wayne Bennett's number two at Brisbane and he followed the England boss to South Sydney.
Marshall is technically already in position, having succeeded Sean Long as assistant to Justin Holbrook six weeks ago. The 43-year-old was a useful back-row forward in his playing days with Halifax, Huddersfield and London Broncos and had his coaching apprenticeship under Tony Smith at Warrington. He was head coach for four and a half years at Halifax, where he ensured the part-time Championship club were top-four contenders every year until his surprise sacking in April.
Watson was a Welsh international scrum-half who gave splendid service to Salford, Rochdale, Halifax, Swinton, Oldham, Leigh and Widnes before carving out a successful coaching career. He began at Swinton before teaming up with his old Wales boss Iestyn Harris at Salford, where he stepped up as head coach in 2016. Constantly working on a tight budget and with a series of off-field issues that would have tested more experienced men, Watson continued to defy all expectations by turning the Red Devils into play-off contenders and his stature was recognised by his addition to the Great Britain backroom team.
It would rank as one of the more unlikely appointments since Wane spent nearly four decades as player, scout and coach at arch rivals Wigan but it cannot be ruled out. Wane, 54, left his home-town club at the end of the 2018 season, shortly after guiding them to a third Grand Final triumph, to take up the part-time role of high-performance coach with the Scottish Rugby Union. But he remains a rugby league man and expressed an interest in the Leeds vacancy earlier in the year.