JD's double quick switch.
The 34-year-old Australian loose forward, left, who has spent the last decade in British rugby league after originally back-packing around Europe, signed a 12-month contract with promoted Championship club York after being released by the Wildcats at the end of the 2010 Super League season.
But he has now performed an about-turn after being given the opportunity to secure his first coaching role.
He will succeed Barry Eaton, who has left the Cougars after five years to become assistant to Crusaders RL head coach Iestyn Harris in Wrexham, and has signed a two-year contract.
Demetriou, who spent the last seven seasons with the Wildcats, was pursued by a host of non-Super League clubs, including Hunslet, Widnes and Dewsbury.