Tuesday, August 19, 2008 - 4:33 PM

Australian athlete Sally McLellan will be looking to spring an upset when she races the final of the women's 100 metres hurdles tonight.

McLellan ran 12.70 seconds to squeeze into tonight's final at the Bird's Nest, finishing fourth in her heat last night won by world number one American LoLo Jones in a time of 12.43 seconds.

McLellan, who grew up on Queensland's Gold Coast, will take to the blocks at around 12:30am AEST on Wednesday morning.

The 21-year-old, who is the first Australian woman to make the 100m hurdles final since Glynis Nunn back in 1984, is also shooting for Australia's first ever medal in the event.

McLellan will need to get past the American trio of Jones, Dawn Harper and Damu Cherry, as well as Jamaican gun Deloreen Ennis-London.