Poor performances in the first two disciplines of the second day - the long jump and the javelin - had left the 28-year-old with too much to do in the two-lap event to take her place behind the gold and silver medallists, respectively Carolina Kluft, who defended her title superbly despite an ankle injury, and France's Eunice Barber.
Kluft, tested as never before, delighted the 40,000 crowd in the Olympic Stadium by taking gold with 6,887 points, 63 points clear, after trailing by two points overnight.
The 30-year-old Frenchwoman took less delight in it, however, claiming at a post-event press conference that Kluft's winning long jump of 6.87m had been illegal. "Was it a foul?" she asked her opponent. "It was very close, but it was not over," said the Swede. At which point Barber turned to the audience with raised eyebrows.
Kluft had begun this competition with her ankle heavily strapped, and when she only managed 1.82m in the opening day's high jump, 12cm off her best, it seemed that Barber, the world champion in 1999, was about to make the most of the 22-year-old Swede's vulnerability. But a personal best of 15.02m in the shot brought the Olympic champion back into the fray.
"I have learnt something this year by this injury," Kluft said. "I have not had an injury before, and when I did it on Friday I thought, 'Can I compete or not?' And after the high jump it was very bad for me. I had to force myself to keep up my positive spirits."
But if Kluft's victory appeared open to doubts of more than one kind, that of another Olympic champion, Justin Gatlin, was entirely predictable as he easily defeated a 100m field which lacked the injured world record holder Asafa Powell in 9.88sec.
The 23-year-old American's time was the second fastest recorded this season behind Powell's mark of 9.77sec. In the Jamaican's absence, the amiable young man whose Olympic triumph came as such a surprise produced a smoothly assured performance, overtaking the leader, his US team-mate Leonard Scott, at the half-way point and surging home to finish a stride clear, with Jamaica's Michael Frater claiming silver in 10.05sec and Kim Collins, the defending champion from St Kitts and Nevis, taking bronze in the same time.
Gatlin, whose winning margin was the largest in the World Championships' history, was in exuberant mood afterwards. "Even if Asafa had been in the race I would have won," he said. "I'm the one who came to the big dance and I stopped the show."
The 100m had already seen a demoralising early departure for Mark Lewis-Francis, who lost in Saturday's second round. And though 200m specialist Marlon Devonish did well to reach yesterday's semi-finals, where he was sixth in 10.24sec, Jason Gardener missed qualifying for the final by one place, finishing fifth in 10.08sec. "I'm gutted," he said. For Britain, it was that kind of day.
Sotherton had produced what she described as "a personal worst" of 33.09m in the javelin, which followed an indifferent long jump of 6.41cm, 27cm adrift of her best, and she left the stadium after the morning session in tears.
But she returned determined to run as never before in an attempt to make up lost ground. Her time of 2min 07.96sec was almost two and a half seconds faster than she had previously managed, but her position remained the same as she finished with 6,325 points.
Going into the last event, the Briton was the equivalent of 13 seconds adrift of the third-placed Margaret Simpson of Ghana, and 12 seconds away from fourth-placed Austra Skuyte, Lithuania's Olympic silver medallist. Given Sotherton's existing personal best of 2min 10.29sec was only seven seconds faster than Simpson's, and five seconds faster than Skuyte's, that was not a feasible target.
"I've got no excuses," said Sotherton, who marked her first season as a full-time heptathlete with an Olympic bronze last summer. "It shows that things are not ingrained in me yet. But one day they may be. I cried my eyes out for about an hour after the javelin - it was abysmal.
"But everyone was telling me I could still do it if I gave the 800 everything I'd got. I thought 2.07 might be enough, but it wasn't to be."
Sotherton's performance was watched from the sidelines by the coach who guided her to the Olympic bronze, Charles van Commenee, who is now performance director for his native Netherlands.
Van Commenee famously greeted Sotherton's unexpected achievement in Athens with an accusation that she had "wimped out" in the concluding 800m and missed a chance of the silver.
"Of course I have been following Kelly's progress here, and I am disappointed for her," he said. "But she is still really a novice at the event in a way, and to finish fifth in the world, well ... I wonder how many other Britons will finish that high?"
The answer to Van Commenee's question will become apparent this week, but it is certainly a pertinent one. Certainly, there will be no opportunities today. Britain have no one in any of the five finals.