Hannah Miley fell short in her mission to win Great Britain's first medal of the 2012 Olympics when she was fifth in a 400 metres individual medley race that saw the first long-course world record set by a woman since the ban on performance-enhancing suits.
Ye Shiwen, just 16, secured China's second gold of the session after Sun Yang's commanding 400m freestyle victory.
Ye, who won the 200m individual medley aged 15 at the World Championships in Shanghai last year, produced a superb freestyle to stretch away and touch in four minutes 28.43 seconds.
Not this time: Hannah Miley finished off the pace in the 400m individual medley
For Miley, it was a disappointment although she was never really in the hunt for a medal. The 22-year-old had been strongly fancied to challenge after her breakthrough on the global stage last year when she was second in the World Championships in Shanghai.
Despite the Garioch swimmer's best efforts, she touched two places outside the medals in 4mins 34.17secs.
Miley, who is coached by her father Patrick in a 25-metre pool in Inverurie, was disappointed but knew she could not have given any more.
She said: 'I'm feeling all right. Most of the media are expecting me to be depressed and down and in tears.
'I know it wasn't the result that the public wanted, which was a medal, but that was something that they decided to put on themselves, to that expectation of me.
Record breaker: Ye Shiwen celebrates her success in the 400m individual medley
'This morning was the fastest heat swim I'd ever done, and it was the same for a lot of the other girls.
'It was just a matter of who could recover the quickest and it was the young ones that won.'
Ye covered the final 100m in an astonishing 58.68 and Miley admitted she had been taken by surprise.
She said: 'That was very, very fast, and it'll be intriguing to look at the analysis and stuff because there are a lot of things that they've obviously taken from us senior ones and learnt from. And, for us, it's an opportunity to learn from them.
'It's just something that it's an absolute a privilege to be part of that race. It's not very often you get to swim in the same water as a world-record holder.
'It would've been lovely to have been up there and challenge that but, at the end of the day, that performance was what I could give and I do apologise to everybody that it wasn't what everyone expected. But, for me, I gave it my all and I can't ask for more than that.'
In at the deep end: Miley was up against it in the final of the 400m individual medley
'It's a very rare opportunity that us GB swimmers get to have. So, I'm really, really happy and it's just an experience that'll live with me forever.'
Sun continued to leave an indelible mark on the global stage just before Ye's triumph.
The 20-year-old was second over eight lengths at the World Championships in Shanghai last year before producing a sublime 1,500m freestyle in which he lowered Grant Hackett's long-standing world record.
While talk of the Chinese swimmer has focused on how far into uncharted territory he can take the longer event, Sun came to London heading the 400m world rankings.
He qualified fastest from a dramatic morning session which had seen defending champion Park Tae-Hwan disqualified and then reinstated.
Well done: Miley congratulate Ye after the race
Sun's time of three minutes and 40.14 seconds was an Olympic record and the 20-year-old was under world record pace until the final metres when he slipped outside.
It surely cannot be so long before he, or another swimmer, breaks it but it demonstrates the advantage of performance-enhancing suits at the back end of a race.
Big winner: Sun Yang celebrates on the podium after winning the 400m freestyle
Sun and Park were in a shoot-out with 100m to go but the former took control on the penultimate length, his languid stroke lengthening.
Carry touched in seventh in 3:48.62, his qualification for the final 'a dream come true' for the Scot who at 30 is the oldest on the team.
Great Britain's Fran Halsall, Amy Smith, Jess Lloyd and Caitlin McClatchey came home in fifth as Australia won the gold medal in the women's 4x100 metres freestyle relay.
The Netherlands took silver with the United States in third.