On Sunday, Olivia Newton-John and Alice Cooper joined local stars 5 Seconds of Summer, Tina Arena and Delta Goodrem for the Fire Fight Australia gig.
Joining Queen's Brian May and Roger Taylor on stage, Lambert filled in for the late Freddie Mercury as the band performed hits such as Bohemian Rhapsody, Radio Ga Ga, We Will Rock You and We Are The Champions.
Delta Goodrem turned heads as she put on a showstopping performance as she rocked the sellout crowd at Fire Fight Australia in Sydney's ANZ Stadium on Sunday.
The 35-year-old songstress looked every inch the pop star in a white shirt and high-waisted metallic pants, while she showed off her Australian pride by holding a flag.
The Australian singer's newly trimmed blonde bob framed her ageless visage while her eye makeup look was all about lashings of mascara.
The You Will Only Break My Heart singer sang a medley of her hit songs which included Innocent Eyes, Born To Try and Sitting On Top of the World.
Delta also performed her latest chart topping hit, Let It Rain, which she wrote specifically about the devastating fires.