The former Great Britain captain and coach cited the resignation of chairman Craig Harrison and the club’s financial problems for his decision.
Rugby League legend Hanley, 47, said: “Craig is leaving and it’s not viable for me to stay while there are financial restraints.
“If the money was there, I’d stay. I’ve loved my time at Doncaster.
“I’m extremely proud of the boys and I’ll watch their careers developing.”
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