Ayana smashes women's 5000m field

Ethiopia's Almaz Ayana has obliterated the women's 5000m field to set herself up for a second Rio Olympics gold medal.

Ayana, who last Friday decimated the 10,000m world record, finished in 15 minutes 4.35 seconds in her heat on Tuesday to qualify fastest overall for Friday night's (Saturday AEST) final.

Australians Madeline Heiner-Hills, Eloise Wellings and Genevieve LaCaze are also through.