He oversaw the gold-medal careers of Olympic stars Jodie Henry and Alice Mills, but Shannon Rollason has quit his role as head coach of the Australian Institute of Sport's swimming program to work in Denmark.
Rollason's decision comes as Swimming Australia conducts an internal review after the sport's lack of success at the London Olympics.
It also comes as the AIS intends to phase out all scholarship programs by the end of this year.
Rollason will take up the position of head coach for the National Training Centre in Denmark and said leaving the AIS, which he joined in 2005, was a difficult decision.
Rollason said he had confidence in the future of Australian swimming and the role the AIS will play beyond 2013 when the planned transition to Swimming Australia's high performance network as the National Centre of Excellence will take place.
"Working in a world class environment like the AIS with world class athletes and world class support staff is what every coach dreams of. The decision to leave was not easy, but I felt the time was right to change path,'' Rollason said in a statement.
Swimming Australia's interim chief executive Jeremy Turner said Rollason's departure would not have a crippling impact on athletes.
''We will work with the AIS to ensure AIS and Australian swimmers continue to get the best possible coaching and support,'' he said.
A spokesman for the AIS said the institute was working with Swimming Australia to find a solution, but the priority was preparing athletes for this year's world championships, in Spain in August.
A final decision on whether there would be a replacement would rest with Swimming Australia, the spokesman said.