Sanya Richards-Ross: Christine Ohuruogu's main rival has unfinished business as she aims to bury Beijing ghost

She has shrugged off illness but can she see off Britain's defending champion? She talks to Simon Turnbull

Sanya Richards-Ross, pictured, has sounded a warning to Christine Ohuruogu, 'Christine, I’m sorry – you cannot dart under the radar any more' (AP)

Sanya Richards-Ross has seen it coming. All year long, while Christine Ohuruogu has been quietly going about the business of preparing for London 2012, sneaking under the media spotlight, Richards-Ross has been expecting the Stratford woman to re-emerge as a major force in the women's 400 metres.

The return to form that Ohuruogu produced at Crystal Palace last Saturday, overhauling the world champion Amantle Montsho in the home straight, did not take her long-term rival from the United States by surprise. "Christine, I'm sorry – you cannot dart under the radar any more," Richards-Ross says by way of a pre-Olympic message to Britain's one defending track and field champion.

"Christine is the Olympic champion and she's also a former world champion, so all of us know her pedigree. Nobody was really concerned with her early-season form. We all know that she usually comes to the major championships prepared.

"I think Christine will be a great rival. I'm looking forward to the meet and I'm looking forward to the race. I hope Christine comes at her best. I'm looking forward to Montsho running well too, and the Jamaicans. I think it's going to be a fantastic final. I hope to be part of it."

It is fair to say that Richards-Ross has unfinished business with the Olympic 400m final. Four years ago in Beijing she entered the home straight with a clear lead and the gold medal in her sights. But then she felt a tightening in her left hamstring. As the Jamaican-born American faded to third, Ohuruogu produced a grandstand finish to take the title.

It came as a crushing blow to Richards-Ross. It was her first defeat of 2008 and it remains her only loss in 20 races against Ohuruogu.

Since that balmy night in the Chinese capital, the Briton has had her battles on the injury front and Richards-Ross (right) has had to deal with a condition that was initially misdiagnosed as the auto-immune disease Behcet's syndrome.

The 27-year-old, who left Jamaica at the age of 12 to settle in Florida with her family, was so badly affected with ulcers in her mouth and on her lips that she had difficulty talking and was forced to write notes to communicate with her coach, Clyde Hart. Training was so painful that Hart, the man who guided Michael Johnson to double Olympic gold in Atlanta, gave her paper cups to bite on.

Richards-Ross won the World Championship title in Berlin in 2009, relieving Ohuruogu of one global crown, but then struggled through the illness in 2010 and 2011, finishing down in seventh in last year's World Championship final.

This year she has returned to form, winning the world indoor title in Istanbul in March and scorching to victory in the US trials in 49.28sec and also qualifying for the 200m with third place in 22.22sec. Ohuruogu's winning time in the rain at Crystal Palace last week was 50.42sec, her fastest for three years.

It is no coincidence that Richards-Ross has finally got on top of her disease. She declines to reveal the exact re-diagnosis but the milder treatment she has been receiving has clearly helped. "I was originally diagnosed with Behcet's but in my heart I didn't feel like I really had that disease," she says. "It just didn't fit.

"I moved doctor and I've started treatment for something else. I'm doing a lot better now, not needing as much medication. I just feel more like myself, and my training has reflected that, so hopefully the worst part is behind me."

Richards-Ross was at the Team USA "media day" in Dallas in May when Lashinda Demus, the 400m hurdles world champion, spoke of the ailing state of track and field in the US. "When we get on the track we know we are taking part in a dying sport," Demus said. "We don't have anyone pulling in viewers on television."

Track and field has long been regarded as a third-tier sport in the US but Richards-Ross begs to differ with her team-mate's terminal prognosis. "I don't think Lashinda meant it in this morbid, negative way that it came out," she says.

"The reporter asked a question about a time in the sport when the Olympics were actually in Atlanta, and so it was a different time. The meet was in America so, of course, American fans were behind it; they were more familiar with the faces that were competing – and so she was asked, 'Do you feel pressure to bring that hero feel back to the US?'

"I don't agree that our sport is dying in the US. I think this Olympics will spark interest again because everybody knows where London is. A lot of Americans have been here and it's an English-speaking country. It'll be the closest thing we get to competing on American soil."

Richards-Ross herself enjoys a higher profile than most of her fellow track-and-field team members because she is married to an NFL star, the Jacksonville Jaguars cornerback Aaron Ross. "A lot of the time when my husband's playing on TV they're saying my name or showing me in the stands," she says. "And so people make that connection – 'Oh, that's that track star we've heard about but never seen,' or they may have heard my name for the first time.

"I do think it helps my profile because so many Americans are tuned into the NFL."

Another thing that would raise the public profile of Richards-Ross would be burying the ghost of Beijing and striking Olympic gold in London.

"I feel so much more mature and I'm just very excited about it," she says. "I feel like I'm living more in the moment now and appreciating the opportunity.

"If I do win that gold medal it's going to mean more to me than I can describe to anybody because I've waited for quite some time and really worked hard for a very long time.

"I dream about it all the time. I just hope that it will become a reality."