ATHLETICS:AS RECENTLY as last Monday you could have scripted day seven inside the Bird's Nest along the lines of the 400-metre champion Jeremy Wariner leading the gold-medal onslaught for the USA before China went to war with Cuba in the 110-metre hurdles.

In the meantime, Alfred Hitchcock must have got his hands on it, because in the end there were more than a few tales of the unexpected. When China's Liu Xiang failed to get over the first hurdle of his event the way was cleared for Cuba's Dayron Robles to win gold, and he took full advantage of the cruel twist of fate for the Chinese superstar.

Robles produced probably the smoothest 110-metre hurdles victory in Olympic history, and he still looked disappointed.

Robles wanted the world record to go with the gold medal. On the night, the 12.93 seconds was six-hundredths of a second outside his own mark of 12.87, but if the 21-year-old from Cuba somehow felt sorry for himself, he should have spared a thought for Wariner.

Since winning the Olympic title four years ago as a 20-year-old, Wariner had been as close to invincible as an athlete can get, winning both editions of the world championships in the years since and running 43.45 seconds, the third-fastest of all time.

Earlier this year, however, the Texan got a little greedy and decided his long-serving coach Clyde Hyde - the old guru of Michael Johnson, among many others - should get a slightly lower percentage of his earnings.

Hyde said no, so Wariner gave himself over to the far less experienced coaching hands of Michael Ford.

Straightaway there appeared chinks in his armour. The 22-year-old LaShawn Merritt from Virginia beat him at the US Olympic trials - and he repeated that feat last night in even more dramatic style as Wariner tied up in the final 100 metres like someone vainly running after the last bus.

Merritt won gold in a lifetime best of 43.75; Wariner faded to second in posting an almost pedestrian 44.74.

Down in the mixed zone, we half expected Wariner to blame his sunglasses, which more resembled skydivers' goggles and surely inhibited his view of the finish.

"No, I just didn't have anything left," he said. "I don't know what to say. I ran the best I could. I'm disappointed with the result, but I'm just worn out.

"It's been a long season. I think I would have won, but you know, things happen for a reason."

Karma, perhaps, although there appeared no reason why Wariner eased up in the end, almost losing out on a medal of any colour. Still, he took silver as his team-mate David Neville followed in third - securing a clean sweep for the USA in one event they at least continue to dominate.

The USA were expected to dominate the sprint relays here too, but - if for no other reason than incompetence - that won't happen.

In last night's heats of the 4x100m, all Tyson Gay had to do was jog down the home stretch, but instead he dropped the baton in the changeover with Darvis Patton, and the Americans were out.

"I'm a veteran. I never dropped a stick in my life. It was my fault," said Gay, who goes from winning three gold medals at last year's World Championships to taking none at all in Beijing.

As a fellow native of America's deep south, Albert King, once sang, if it wasn't for bad luck, he'd have no luck at all.

The Americans were just about getting over the shock of that when the women's 4x100m team did exactly the same, the equally experienced Torri Edwards the guilty hand this time.

It means Jamaica are now practically certain of winning both sprint relays, giving Usain Bolt his third gold medal in the process.

Jamaica mined further gold on the track last night to underline their status as the new world leaders in sprinting, with the US once again the nation to suffer.

Veronica Campbell Brown had failed to make the team in her better event, the 100 metres, so she won Olympic gold over 200 metres instead, clocking 21.74.

Allyson Felix, the world champion, at least took silver for the US as Kerron Stewart took the bronze for Jamaica.

As recently as last Saturday, the idea of the Americans having no representation in the final of the men's long jump and triple jump would have sounded outlandish, but so it proved.

It certainly made for an interesting competition, and while Britain's Phillips Idowu was the long-time leader, Portugal's Nelson Evora got up for gold with a fourth-round jump of 17.67.

"I can't believe I'm standing here disappointed with silver, but I am," said Idowu. "I would have loved to have gone to London in 2012 as defending champion."

Still, Britain's exceptional medal haul continues to grow.

And as recently as yesterday afternoon, the chances of the season's two fastest 800-metre runners in the world both being eliminated in the semi-finals would have been laughable, but so it proved too.

Russia's defending champion, Yuriy Borzakovskiy, was run out of it in the final metres of his semi-final, ending up third and missing out even as a fastest loser. And the teenage Sudanese sensation Abubaker Kaki, who earlier this year won the world indoor and world junior titles, finished a spent-looking last in his race.