A rejuvenated Dani Samuels stayed cool when the heat was on, producing her best throw in more than two years to power into the Olympic discus final.
Long jumpers Mitchell Watt and Henry Frayne also did enough to qualify for their final on Saturday night, but it was 2009 world champion Samuels who produced the stand-out Australian performance on day one of the London Games track and field program.
After a middling effort of 60.02m and a foul in the opening two rounds of qualifying, Samuels - the 2009 world champion - needed something big with her final throw.
And she delivered right on time with 63.97m - good enough for seventh place overall.
"I'm really happy with that, especially with the distance in the end," said Samuels.
"It's a season best and something I haven't reached since 2010 so I'm pumped.
"I wasn't panicked because it only takes one throw.
"I got my nerves out of the way after I was a little bit too tense for the first couple."
Watt (7.99m) and Frayne (7.95m) didn't achieve anything outstanding in the long jump qualifying round.
But at least they got through to Saturday's final in ninth and 11th place respectively which is more than could be said for defending Olympic champ Irving Saladino from Panama, who bombed out with three straight fouls.
"I can't believe I'm in the Olympic final jumping 7.99," said the 24-year-old Watt.
"It was a bit tricky out there and if it's the same tomorrow night, it might just be whoever's lucky on the board and who gets the right wind.
"There's absolutely no advantage in jumping big in a qualifying round.
"The plan was to do as little as possible and I feel like I didn't do much at all."
Melissa Breen ran headlong into a firestorm in the first round of the women's 100m.
Six women broke the 11-second barrier - double the number to have ever done so before in the Olympic heats - headed by reigning world champion Carmelita Jeter from the United States (10.83).
Breen was eliminated after clocking 11.34 to finish sixth in a heat won by defending Olympic champion Shelly-Ann Fraser-Pryce from Jamaica (11.00).
"There's obviously a sense of disappointment because I would have loved another run, but those girls are running ridiculously fast," said the 21-year-old Breen.
In other Australian action at the Olympic Stadium, Brendan Cole (a personal best of 49.24) and Tristan Thomas (49.13) both moved through to the semis of the 400m hurdles and Ryan Gregson advanced to the 1500m semis despite finishing ninth in an exceedingly fast heat.
Australian Eloise Wellings trailed home last in a women's 10,000m final won commanding style by Ethiopia's Tirunesh Dibaba in 30 minutes 20.75 seconds.
Dibaba also won the 5000-10,000m double four years ago in Beijing and is a four-time track world champion.
The other gold medal decided on day one went to Tomasz Majewski of Poland in the men's shot put with 21.89m.