Last night it stung the medal hopes of Scotland's Hannah Miley and Michael Phelps's dreams of adding to the greatest career in the history of the sport.
The 21-year-old Scot from Inverurie finished fifth in 4:34.17, trailing in the wake of 16-year-old Chinese Ye Shiwen, the world 200m medley champion, who broke the world record with her winning time of 3:40.14.
Miley was never near the pace or in the medal mix, turning last after 50m, seventh after 100, sixth at 200, before moving to fifth on the breaststroke and maintaining that position with 50m to go.
"I gave it absolutely everything I had," Miley said. "It was a real job getting into the final, and it was who could recover quickest. I'm disappointed I couldn't get a medal, but I could not have given more. I apologise to anyone who had high expectations for me."
The last individual Olympic swim medal by a Scot was won 60 years ago today by Elenor Gordon in Helsinki. She watched on TV at home in Hamilton.
Phelps finished fourth in the 400 metres medley and out of the medals for the first time in his Olympic career in his last Games. His US rival, Ryan Lochte, took the gold in 4min 5.18sec ahead of Thiago Periera of Brazil (4:08.86) – last in Beijing – with Japanese Olympic debutant Kosuke Hagino (4:08.94) taking bronze. The 27-year-old Phelps only ever threatened when emerging second after the opening 100m butterfly, and was timed at 4:09.28. Lochte took over after the 'fly and was never overtaken.
It may be premature to hail this as the end of the Phelps era, but there was a sense of just that last night, even if his world record from Beijing survived.
It is certainly the beginning of the end for the big American, and the end of the beginning for his compatriot Lochte, the first man to have beaten him three times.
Lochte won bronze behind Phelps, but has since become the world's strongest swimmer by hurling tyres and dragging chains, and won world gold in 2011 and 2009. He was only third fastest qualifier for the final.
Phelps arrived with 14 Olympic gold medals and two bronze, and the goal of becoming the most prolific Olympic medallist ever, which would require him to win three medals. Nine of his golds were in individual events, the other five being in relays.
Phelps had won Olympic gold in this event in Beijing and Athens, and was attempting to become the first male swimmer to win the same individual discipline in three successive Games.
The writing was on the wall, however, in the morning heats, as he was eighth fastest and last to qualify. He was spared exclusion by 0.07 of a second (4.13.33 in the heat). Laszlo Cseh, of Hungary, behind him in ninth, wanted gold to complete the set in this event.
Phelps has three more shots at his defining 19-medal goal – 200m butterfly, 200m individual medley, and the 100m butterfly. He will also contest all three relays, but could not have emulated his so-called great trawl of eight titles in China, having entered only seven events.
David Carry, 31 – the oldest man in the GB swim team – set the seal on an outstanding career when he finished seventh in the 400m freestyle in 3:48.62. It was the Aberdonian's first individual final in his third Olympics.
Carry, who won double Commonwealth gold and relay silver in Delhi two years ago, is heading for retirement and marriage in September to Keri-Anne Payne, the world open water champion and defending Olympic silver medallist, who also swims here, and was cheering him on. Carry said reaching the final was "a dream come true" after making the team at the final hurdle less than six weeks ago.
He was second in his heat (3:47.25), seventh fastest going into the final, but there was anguish for his compatriot Robbie Renwick who missed out, finishing tenth in 3:47.44.
Victory went to a second Chinese, Sun Yang, in an Olympic record of 3:40.14. Korean Olympic and world champion, Park Taehwan was disqualified for a false start, but then reinstated, finishing second in 3:42.06.
Ellen Gandy was fifth in her 200m butterfly semi-final with 57.68 and reached tonight's final, but Fran Halsall missed out, seventh in 58.52, three tenths outside her qualifying time. Edinburgh's Craig Benson smashed his personal best with 60.04 in the heats of the 100m breaststroke, and joined Michael Jamieson in the semis. The Olympic record fell in the first semi, with 58.83 from South African Cameron van der Burgh. Jamison finished third in 59.89, but it was not enough to make the final. Benson was 14th overall. GB women finished fifth in the 4x100m relay as Australia took gold.
Spectators last night indicated they thought they were being stung, too. Many seats in the 17,500 swimming arena – especially the £450 top-priced ones – lay empty, prompting further calls for an inquiry after £2012 and £1600 seats at the opening ceremony were unused. Lord Coe has said he will name and shame sponsors who bought seats then failed to show.