Daly will return to the Open at New South Wales Golf Club in Sydney from 3-6 December and expects to be back near his best after a year of transformation.
"I am looking forward to returning to play the 2009 Australian Open and am particularly excited about playing the course at La Perouse for the first time. I have heard so many great things about the course," Daly said.
"Long John" Daly won the US PGA Championship in 1991 and the British Open in 1995 and remains one of world sport's great characters and most popular players.
Daly will be sporting a lighter frame when he returns to the Australian Open for only the third time, having shed 20 kilograms following recent lap-band surgery.
The American will be joined at La Perouse by Australians Mathew Goggin and Stuart Appleby who have also confirmed their attendance at the Championship.
Goggin, who finished runner-up to South African Tim Clark in the 2008 championship, will hope to go one better in 2009 as Appleby shoots for his second crown after winning in 2001.
Golf Australia CEO Stephen Pitt said he was pleased to have Daly, Goggin and Appleby vying for the Stonehaven Cup.
"As soon as the Australian Open title is on the line, there's always a strong field who are driven by the thought of becoming the Australian Open champion and joining one of the most exclusive roll calls in world golf," Pitt said.
"This field is already impressive with some real crowd favourites and it will only get better over the next few months."
The 2009 Australian Open will be the first Australian championship on the new One Asia Super Series schedule.
The 2009 Australian Open will be held at the New South Wales Golf Club, La Perouse from 3-6 December.
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