Bolt, Farah sign off in spectacular style at London Games

But Saturday's sporting highs were tempered by news that a Syrian runner was expelled from the Games for doping and a South Korean football player was barred from a medal ceremony for staging a political protest after a bronze playoff with Japan.

In a day brimming with golden opportunities - 32 titles were up for grabs - Bolt kissed off his one-man Olympic show to lead Jamaica home for gold in a blistering relay that brought London's track and field events to a shimmering close.

Bolt added that title to the ‘double double' he won in the 100 meters and 200 meters, defending both after his Beijing triumphs and writing his way into Olympic history as one of the finest -- and zaniest --sprinters the world has known.

As he crossed the line, Bolt cupped his hands in an “M” shape above his head -- a nod to Farah who had earlier run away from the pack to win the hosts' first men's 5,000 meters gold.

“It's always a beautiful feeling to end off like this,” Bolt said. The quartet of Bolt, Yohan Blake, Michael Frater and Nesta Carter darted around the track in 36.84 seconds, beating their own record and leaving the United States trailing in their wake.

Farah, who snatched the 10,000 meters crown in London just days ago, is the seventh man to win both races at the same Olympics and the trailblazer of a British team that has claimed more medals than at any Games in more than a century.

“I wanted a gold medal for each of my two girls on the way,” said the 29-year-old, whose wife Tania is heavily pregnant. “They could come any day now.”

Russia's world champion Mariya Savinova saw off South African Caster Semenya to win the women's 800 meters, the U.S. triumphed in the women's 4x400 meters relay and Trinidad and Tobago's Keshorn Walcott struck a surprise gold in the javelin.

Doping cloud

The final few moments of Olympic glory in track and field bring a close to an eventful penultimate day of the Games in which startling athletic prowess did not always dominate the headlines.

Syrian athlete Ghfran Almouhamad, who competed in the women's 400 meters hurdles, was the 11th athlete to be thrown out of the Games since the start of the Olympic period, which began on July 16, after testing positive for a banned substance.

The 10-strong Syrian team has attracted considerable media attention during London 2012, less for its sporting achievements than the bloody conflict raging at home between the opposition and forces loyal to President Bashar al-Assad.

Politics also crashed the party when the International Olympic Committee (IOC) called for a South Korea football player to be banned from a medal ceremony after he held up a poster referring to his country's long-running territorial dispute with Japan - after the two teams had just battled for the bronze.

Five-time world champions Brazil's long quest for Olympic football gold continues after Mexico stunned the usually stylish South Americans with a 2-1 win. Brazil's women provided some consolation, beating the United States to gold in the volleyball.

The upsets spread to the pool where Chinese divers Qiu Bo and Lin Yue could not better the efforts of American David Boudia in the 10 meters event. Qiu won silver and Britain's Tom Daley, cheered on by English football player David Beckham, took bronze.

In the ring, Ukraine's Oleksandr Usyk claimed the men's heavyweight crown while classy light-welterweight Roniel Iglesias Sotolongo won Cuba's first boxing gold in eight years and Britain's Luke Campbell took the bantamweight title.

The hosts have claimed 28 gold medals, comfortably beating their Beijing tally of 19. It puts them third in the overall medals table, which the United States top on 44 to China's 38.

With one day of Olympian effort left, Sunday's highlights include the toughest running event - the marathon - and the showcase men's basketball final, which sees pre-tournament favorites the US taking on a dangerous Spain side.

The Spice Girls, One Direction, George Michael and The Who were expected to perform as London  bid goodbye to what the Guardian newspaper dubbed the “feelgood Game.”

Games chief Sebastian Coe declined to compare London with other Olympics, but said simply: “I'm pretty pleased with the way we've delivered.”

“Party, party, party,” he told a news briefing when asked to describe the closing concert ending a drama-filled few weeks.