James Magnussen went some way to exorcising the failure of Australia's sprint freestyle relay team with a solid 100m heat performance.
The world 100m freestyle champion was in the Australian quartet - dubbed by some as the 'Weapons of Mass Destruction' - who were heavily backed to depose the United States as Olympic champions.
However, they failed to even make the podium as France overhauled the USA in the final metres to take gold.
Magnussen, known as 'the Missile', is a hot favourite to add the Olympic title to the world gold he secured last year in Shanghai and has clocked 47.10 seconds already in 2012.
On Tuesday, he qualified fourth overall in 48.38secs, with American Nathan Adrian fastest in 48.19.
Magnussen said: "I think it was a step in the right direction, it was a good swim.
"It's an improvement from the other night, I am keeping positive with a smile on my face.
"I took a fair hit in the relay, I am still trying to bounce back from it.
"It was one of my first failures since breaking into the international scene."
Daniel Gyurta headed the 200m breaststroke heats while the United States qualified fastest for Tuesday night's 4x200m relay final in 7:06.75.
There was a shock in the women's 200m butterfly where British world silver medallist Ellen Gandy finished 17th, with America's Kathleen Hersey leading the way in 2:06.41.
In the badminton, former Olympic champion Taufik Hidayat came through a tough battle with Spain's Pablo Abian to reach the knockout phase.
The 2004 gold medallist was game point down in the first game of what was effectively a shootout for a place in the last 16 at Wembley Arena but came back to win 22-20 21-11.
India's Kashyap Parupalli sprang a surprise to advance at the expense of 10th seed Tien Minh Nguyen of Vietnam.
The world number 21 produced one of the best performances of his career to win 21-9 21-14 and top Group D.
World champion Denisse van Lamoen was dumped out in the first round of the women's individual archery competition at Lord's.
Van Lamoen, who was Chile's flagbearer at the opening ceremony and is the country's current athlete of the year, was paired with the player she defeated for world gold last year - Georgia's Kristine Esebua - and was bundled out in straight sets.
Both players were well short of their best in the ranking round, hence lowly seedings of 31 and 34, but Esebua found her feet to win 6-0.
Esebua could not pull off another big win, though, and was soon defeated by second seed Lee Sung-jin of South Korea.
In the men's event, Michele Frangilli could not follow his heroics in the team competition and was knocked out of the individual in the first round.
Frangilli claimed gold for the Italian trio when he struck 10 with the last arrow of the final but his touch deserted him as Ukraine's world number three Dmytro Hrachov claimed a 7-3 victory.
Hrachov himself became a big-name scalp when he lost his last-32 encounter with Japanese fifth-seed Takahuru Furukawa.
South Korea's Kim Jae-bum remained on course for Olympic success in the judo as he swept into the semi-finals of the men's under-81kgs at ExCeL.
The world champion, a silver medallist at Beijing in 2008, will take on Ivan Nifontov for the chance to fight for gold after the Russian ended an impressive run by Canada's Antoine Valois-Fortier, which included victories over European champion Elnur Mammadli of Azerbaijan, who had won Olympic gold at under-73kg in Beijing, and Britain's Euan Burton.
There was a shock in Pool B, however, where top seeded Brazilian Leandro Guilheiro was beaten by American Travis Stevens and so goes into the repechage for the chance to fight for bronze.
German Ole Bischof, the world number four, also made the semi-finals and will face Stevens in Tuesday afternoon's medals block.
Germany claimed the gold in the team eventing at Greenwich Park.
Great Britain, whose team included the Queen's granddaughter Zara Phillips, took silver with New Zealand third.
In the hockey, defending Olympic women's champions Holland edged out Japan 3-2 and New Zealand beat South Africa 4-1.
Spain, fancied to push the United States in the men's basketball, saw off Australia 82-70 while Russia crushed China 73-54.
