Pop star Avril Lavigne stole the thunder from rival Justin Timberlake by taking two top prizes at the MTV Europe Music Awards on Thursday.

The 23-year-old won Most Addictive Track for "Girlfriend" and the coveted Solo Artist of 2007 category while Timberlake, who dominated the event in 2006 and was the most nominated artist in 2007, came away empty-handed.

Britain's Amy Winehouse collected the Artists' Choice award but her live performance of "Back to Black" at the packed OlympiaHalle in Germany will have done little to allay concerns after drug-related problems.

She accepted her award with a brief "Thanks" before walking off stage. Minutes later she stumbled through her song with a thin, wailing voice instead of the rich growl that has won her so many fans.

Winehouse appeared to have trouble remembering the words to her own song, her dancing was stilted and out of step and she was unsteady on her feet.