Christine Ohuruogu, running the last leg of the 400m relay heats, narrowly avoided failing to reach today's final when she slowed down on the line and nearly lost the third qualifying place to the fast-finishing Claudia Hoffman. Thankfully for Britain's medal aspirations, the individual 400m champion glanced up at the screen in time to realise her predicament and an urgent burst of acceleration took her clear of her German opponent by seven-hundredths of a second.
Ohuruogu took over in second place on the final leg thanks to the efforts of Nicola Sanders, heptathlete Kelly Sotherton – called in following the torn thigh muscle suffered by Lee McConnell – and 800m specialist Marilyn Okoro. "I was just told to qualify so I was taking it easy but I didn't see the German," Ohuruogu admitted.
Britain will also have a chance of a medal in today's men's final, following their quartet's victory in 2min 59.33sec, the fastest qualifying time.
Tirunesh Dibaba won the race-within-a-race against fellow Ethiopian Meseret Defar to take gold in the 5,000m final, the world record holder breaking decisively for home at the bell after a slow, cagey race.
Jade Johnson, who finished seventh in long jump with an effort of 6.64 metres, called for doping cheats to be banned for life after the gold medal went to Brazil's Maurren Maggi, who served a two-year ban in 2003.
"The most annoying bit for me is that a drugs cheat came back and won the Olympic Games.
"I don't think that anyone should be allowed back, regardless," said the former European silver medallist. "I would still have only come sixth but the girls a few down the line would have got a medal. I was hoping anyone would beat her.
"I think people should be banned for life if they take drugs, simple as that. Two years is not long enough. I'm sure you must still have it in your system, you still must have benefits. If you're going to cheat you should suffer the consequences."
Maggi won with her opening effort of 7.04m, although Russia's Tatyana Lebedeva almost kept her title with a last leap of 7.03m. Bronze medallist Blessing Okagbare, of Nigeria, only made the final after Ukraine's Lyudmila Blonska – who had been second-highest qualifier – was thrown out of the Games after confirmation that she had tested positive for drugs for the second time in her career.