OSAKA, Japan, Sep 3: American Tyson Gay's explosive sprint treble highlighted his country's continued track dominance at the world athletics championships.
As the Americans celebrated, hosts Japan scratched their heads as the inquests began into how they won just a solitary bronze on the final day in Osaka yesterday.
After crushing world record holder Asafa Powell in the 100 metres, Gay added golds in the 200 and 4x100 relay to become the second man to achieve the feat at a world championships.
Allyson Felix completed a hat-trick of her own after retaining her 200m crown and added victories in the 4x100 and 4x400 to equal East German Marita Koch's three gold medals in 1983.
Meanwhile, Jeremy Wariner edged closer to mentor Michael Johnson's world record with a supreme victory in the men's 400m final.
The United States won 14 gold medals to equal their tally from the 2005 worlds in Helsinki and signal their intent ahead of next year's Beijing Olympics.
Gay's devastating victory over Powell set the tone as he powered to his first major title in an electrifying 9.85 seconds.
Powell finished third, admitting after the race he had ''panicked'' when Gay caught him after 50 metres.
Gay had already added gold in the 200m when he rubbed salt into Powell's wounds by leading the U.S. to victory over Jamaica in the 4x100 on the final day.
The only man to have previously won the sprint treble at a single world championships was fellow American Maurice Greene in 1999. Gay is set to attempt a repeat at next year's Olympics.
''I want to do all three in Beijing,'' he told Reuters. ''Never in a million years did I think I would win three gold medals.''
Felix swept to her second 200m title in dominant style, winning in 21.81 to foil Jamaican Veronica Campbell's hopes of a sprint double.
Wariner was unstoppable, storming to victory in the men's 400m in 43.45 and then helping the Americans destroy their rivals in the 4x400 with the third-quickest relay run ever.
Only Johnson, who set the current world record of 43.18 in 1999, and Butch Reynolds have run quicker in the 400m -- an event the Americans have virtually made their own.
The US underlined their dominance by becoming the first country to sweep all four relays in world championships history as the gold rush continued until the end.
Kenyan-born Bernard Lagat, who only became eligible to represent the US this year, won a unique 1,500 and 5,000 double to show there was more to the American team than sprinting.
The Americans did not have a monopoly on star quality.
Russia's pole vault queen Yelena Isinbayeva flounced into Osaka for just long enough to retain her world title, although she failed to break her own world record of 5.01.
China's Olympic champion Liu Xiang coped superbly with the intense pressure on him ahead of the Beijing Games by storming to his first world title in the 110m hurdles.
Kenya finished second in the medals table behind the US with five golds, three silver and five bronze, bookmarked by wins for Luke Kibet and Catherine Ndereba in the two marathons.
Irving Saladino claimed Panama's first world championship gold medal with a dramatic last-gasp victory in the men's long jump.
''It was like having an out-of-body experience,'' said the 24-year-old after soaring 8.57 metres to confirm his status as the man to beat in China.
Christine Ohuruogu gave British athletics a lift by winning an emotional gold medal in the women's 400m on her return from a year's ban for missed doping tests.
Japan, however, were only spared the embarrassment of finishing without a single medal on the last day thanks to Reiko Tosa's brave bronze in the women's marathon.
The world records promised by organisers failed to materialise -- not one tumbled, largely due to Osaka's fierce heat.
The biggest anti-doping programme in world championship history, meanwhile, uncovered just ''one suspicious result,'' the IAAF said.
The athlete involved can expect a call next week.