QF36 left Singapore at 7.30pm yesterday and touched down in Adelaide at 5am (ACDT) today.
The airline has confirmed the flight was diverted due to a technical issue and landed normally.
It did not make an emergency or priority landing.
All customers have now been moved onto alternative flights to Melbourne.
“We’re very sorry for any inconvenience caused, particularly at this time of year, however safety is our number one priority and we thank passengers for their patience and understanding,” the airline said in a statement.
The aircraft will be inspected by engineers.