Garrett took to the stage after a day on the benches in parliament
Australian Environment Minister Peter Garrett left parliament behind to rock with his old band Midnight Oil for victims of the recent bushfires.
The politician and former lead singer performed in Canberra on Thursday for the first of two practice gigs before the Sound Relief concert on 14 March.
Garrett last performed with the group for a tsunami benefit in 2005.
After spending the day in parliament he joked on stage:"The only person who has to go to work in the morning is me."
Before the gig, 55 year-old Garrett told Australian newspaper The Herald Sun: "Getting ready for a big benefit concert means playing lots of songs fast and loud."
Midnight Oil rose to fame in the 80s with hits like Beds are Burning and Blue Sky Mine. Their lyrics were often politically radical, with the album Diesel and Dust calling for Australia to be given back to the Aboriginal people.
The band broke up in 2002 after frontman Garrett announced he was leaving to go into politics.
He was elected to parliament in 2004 and was made Environment Minister three years later.
There was some speculation that the band would select less political tracks now that their frontman is part of the establishment. Nonetheless the band performed anti-mining song Blue Sky Mine and anti-war song When the Generals Talk.
Following the concert, Garrett told online paper The Australian: "The band and audience were in top form last night and I'm feeling fine."
"Any rustiness was well and truly blown out by the end of the first song" he added.
Some 80,000 fans are expected at the Melbourne gig on Saturday. Other acts on the bill include Jack Johnson, Gabriella Cilmi and Wolfmother, with Kylie Minogue as MC.
A second benefit in Sydney, also on Saturday, will be headlined by Coldplay.
The concerts will raise money for victims of Australia's recent natural disasters.
In January and February the worst fires in the country's history claimed 210 lives in the south, whilst floods swept Queensland in February.