Jessica Ennis's Olympic dream was left in tatters last night after a scan revealed that she had broken her right ankle and would be unable to compete in Beijing. It is a horrible blow for one of Britain's most popular medal prospects and a kick in the teeth for a team already reeling from the news that Paula Radcliffe has a fractured femur.

Dave Collins, the UK Athletics performance director, had said that he hoped people would not “get all Chicken Licken and say the sky is falling down” when Ennis was forced to pull out of the HypoMeeting in Götzis, Austria, last Saturday, but even the most optimistic patriot must now fear the worst for the Olympics. Ennis, fourth at last year's World Championships, was an outside bet for a gold in the heptathlon after making strides in her weaker events, the javelin and the shot, but her absence - and injuries elsewhere - mean the Great Britain team may be looking at middling results rather than medalling ones.

Questions will be asked about the wisdom of Ennis competing in Götzis when she knew she had a niggling problem. It is unclear whether the stress fracture happened in Austria or Sheffield, where she is based, but Ennis admitted that she had felt some soreness in the joint before flying out for the biggest heptathlon in the build-up to Beijing.

A woman who admits to crying easily did her best to present a stiff upper lip. “I'm obviously upset with the results and I'm gutted to be missing out on my first Olympics, but injury is part of life as a heptathlete,” she said. “I am determined to make a full and speedy recovery from this and enjoy a long athletics career.”

Time is on her side. Ennis is only 22, but with Carolina Klüft, the heptathlon queen, abdicating to take up the long jump, she was elevated to immediate medal prospect.

Ironically, after the injury flared up during the high jump on Saturday, Ennis responded to intensive physiotherapy to record three personal bests in the shot and run 23.59sec in the 200metres. She finished the first day ahead of Lyudmila Blonska, the Olympic favourite.

Britain will still have an excellent chance of taking gold in Beijing through Kelly Sotherton, who said: “I'm utterly speechless. I can't even begin to imagine how Jess must be feeling now. I know that I would be devastated. This is a cruel blow for her and I'm so sorry that she won't be out competing with me in Beijing, but she is a strong athlete and I wish her all the very best for a speedy recovery.”

Ennis flew home from Austria early on Sunday morning and had both CT and MRI scans at the Olympic Medical Institute, at Northwick Park Hospital, in Harrow, northwest London. Instead of building up towards Beijing, she will now begin a rehabilitation programme and look to 2012, when she is more likely to be at her peak.

That is no silver lining for a potential golden girl, although her coach, Toni Minichiello, tried to salvage some thread of hope from a traumatic day. “Jess has a long athletics career ahead of her that will sadly not include the 2008 Olympics, but will include London 2012 and the 2016 Games,” he said. “There was nothing in her training or in her PB performances that we've seen over the past few weeks to indicate that an injury of this nature was present.”

Ennis's woes add to an alarming injury list. Doctors have told Radcliffe that it will be impossible for her to compete in Beijing, although she is defying that opinion and fighting hard. She is off her crutches and has started aqua-jogging. Nicola Sanders. the 400metres world silver medal-winner, is sidelined with a knee injury and Sotherton missed Götzis because she was recovering from a kidney infection. Mark Lewis-Francis, a key member of the 4x100metres relay team, is already out of the Olympics after tearing his Achilles tendon.

— A woman who admits to crying Michael Johnson is to return to the IOC the Olympic gold medal that he won as part of the United States 4 x 400 metres relay team at the Sydney Games in 2000. Johnson, 40, who won five Olympic golds in a glittering career, said that his decision followed the confession by Antonio Pettigrew - a fellow member of the US team - during the perjury trial of Trevor Graham, the disgraced American coach, that he used performance-enhancing drugs. “I know that the medal was not fairly won and that it is dirty,” Johnson said. “I feel cheated, betrayed and let down.