A Dutchman who had been given only a slim chance of survival after being diagnosed with leukaemia won one of the Olympics most gruelling events today, the marathon open-water swim.
Maarten van der Weijden was diagnosed with leukaemia seven years ago but pulled through after a stem cell transplant and a course of chemotherapy.
He battled back to become the world's leading open-water swimmer and timed his surge to perfection to win a sprint finish after a three-man fight for gold in the Games' inaugural 10km men's race, after a contest lasting nearly two hours.
"That makes it extra special," van der Weijden said when asked about his recovery from cancer. "It proves that even after such an illness you can win gold."
World open water champion Vladimir Dyatchin of Russia was less happy, disqualified for twice dunking fellow swimmers under the water in the rush to get drinks at scheduled stops.
Relentless rain descended on Day 13 of the Olympics, but failed to deter walkers, decathletes and bikini-clad women playing out the medals games in beach volleyball.
Nothing could dampen the buzz around Jamaica's Usain "Lightning" Bolt, celebrating his 22nd birthday on Thursday after winning a second sprint gold and setting another world record the night before, in the 200 metres.
There was a rap on Bolt's knuckles, though, from the head of the International Olympic Committee (IOC), who said the sprinter was on a par with great U.S. sprinter Jesse Owens but should show more sportsmanship to his competitors.
"I think he should show more respect, shake hands, give a tap on the shoulder to the other ones. Not making gestures like the one he made," Jack Rogge told Reuters. "He still has to mature."
Rogge was referring to Bolt's world-record-breaking win on Saturday in the 100 metres, when he pounded his chest before crossing the finishing line, and celebrated in exuberant style.
Jamaican coach and former sprinter Don Quarrie defended Bolt, saying his celebrations were just youthful high spirits, from a man who is "playful, funny, happy".
The finals of women's beach volleyball went ahead in the rain. An excited home crowd sheltered under umbrellas and multi-coloured ponchos to cheer every point as China's Tian Jia and Wang Jie took on U.S. pair Misty May-Treanor and Kerri Walsh.
The U.S. defending champions won in straight sets, but China were consoled by silver, as well as bronze for another pair, their first medals in the sport.
Afterwards May-Treanor and Walsh, who have dominated the sport for five years and never lost a set at the Olympics, left the door open to a return in London 2012, but said that might depend on plans to have children. Russia's Olga Kaniskina led from the start to win the first gold of the day in the women's 20km walk.
JAMAICA, U.S. SHOWDOWN
The limelight returns to the Bird's Nest in the evening, and another intriguing showdown between Jamaica's extraordinarily successful sprinters and the United States.
Jamaican women have already followed Bolt by sweeping the 100m medals and a trio of strong sprinters are looking to add 200m glory.. The Americans, the traditional superpower of sprinting, are desperate for at least one gold.
Also looming on Thursday is the 110m hurdles final, which was shaping into one of the high points of the Games but is now deflated by the absence of Chinese favourite Liu Xiang.
The Olympic champion limped from the track before his first race, leaving Chinese fans in tears and clearing the way for Cuban world record-holder Dayron Robles.
"I'm very calm. I'll win the gold medal," he said.
The Chinese can at least console themselves with a look at the gold medal table, where they have built up a seemingly unassailable lead of 45 golds to the Americans' 27.
In Athens the U.S. team topped the medals table with 36 golds to China's 32, but the hosts have invested heavily in selecting and training their athletes over many years, an effort that mirrors the nation's growing global economic and political clout.
"The world has to learn to live with a change of geopolitical nature," the IOC's Rogge said, adding that China's sporting success would last "as long as their sports system lasts".
On a packed day of athletics, Americans Jeremy Wariner and LaShawn Merrit go head-to-head in the 400m on Thursday too.
The decathlon began in morning rain, with Bryan Clay of the U.S. building a comfortable lead after the first three events, the 100m, long jump and shot put.
Later, the women's soccer tournament wraps up with the U.S. team facing Brazil and hoping to repeat their victory against the South Americans in Athens four years ago.