Her operatic rendition of Zero Gravity, a song about her experience of postnatal depression, saw her flying through the air atop a pole, flanked by two backing vocalists.

Australia joined the Eurovision Song Contest in 2015 and have scored consistently well each year but never won.

Since rehearsals began in Tel Aviv last week, Miller-Heidke's performance has been the subject of increasing interest.

Iceland's Eurovision Song Contest entry Hatari made a shocking semi-final debut as they performed in leather and latex against a backdrop of pyrotechnics.

The techno-punk group attracted much attention in the lead-up to this year's contest on Tel Aviv, Israel, with their darkly energetic track Hatrio Mun Sigra (Hatred Will Prevail).

They received the night's loudest cheer, combining dance music, heavy rock and pop in front of an international audience at the Expo Tel Aviv.

The UK, as one of the "big five" countries, along with France, Germany, Italy and Spain, are already assured of a place in the grand final.

Last year's winners Israel also do not have to qualify via the semi-finals.

Australian Associated Press