To say that the United States is bracing itself is overdoing it because, when it comes to track and field, it sometimes seems that the country is beyond caring. However, the trial that begins in a San Francisco federal courtroom today has the potential to deliver a blow of unfathomably damaging proportions.

Trevor Graham, one of the most successful coaches in history, is on trial for perjury, for allegedly telling federal investigators that he had never supplied banned substances to his athletes. Given that ten of his charges, including Marion Jones, Justin Gatlin and Tim Montgomery, have been suspended or disciplined for doping offences, his position would seem an unenviable one.

The real mess, however, lies in the testimony of the next few days as both the prosecution and defence have suggested that an A-to-Z of new, unknown drugs cheats may be named and shamed in court. The stats, as they appeared in The New York Times last month, are terrifying, with the prosecution's star witness, Angel Heredia, a Mexican former discus thrower and self-confessed supplier of performance-enhancing drugs, claiming to have the evidence to bring down 12 athletes who between them won 26 Olympic medals and 21 World Championships.

Of those 12, apparently, eight had not been previously linked to doping. As a taster, Heredia threw in one of the biggest names of all, Maurice Greene, which means that four of the past five Olympic 100 metres winners have thus been besmirched (Ben Johnson, 1988; Linford Christie, 1992; Greene, 2000; Gatlin, 2004). Greene has denied any wrongdoing, but only Donovan Bailey (1996) has a reputation that is intact.

With the next Olympics on the horizon, it goes without saying that this is hardly a good time for athletics to be mired in another scandal. It does not help much, either, that Montgomery was sentenced last week to 46 months’ prison for cheque fraud or that he is still facing charges of trafficking heroin, or that Gatlin, who has twice failed dope tests, will be in court arguing his right to run in Beijing. How the mighty have fallen.

All of which may explain why the US, where the interest dial in track and field has always been pretty low, appears to be close to switching it to off. One indicator is that NBC, the Olympics broadcaster, lobbied for the Beijing Games schedule to be rejigged, with swimming and gymnastics moved to the morning so that they could be shown live in the US. Athletics, traditionally the blue-riband event, was not a priority.

Meanwhile, here in a Los Angeles suburb yesterday, there was an athletics meeting featuring a stellar cast, yet the Los Angeles Times weekend edition failed to credit it with a single word. Even sadder was a crowd turn-out that may have tipped 3,000. The names on show included Tyson Gay, the double world sprint champion, and Jeremy Wariner, the finest quarter-miler on the planet, both of whom filled their premeeting press conference not only by sharing the kind of hopes for an Olympic year that you might expect of young men with the world at their feet, but also by urging the public not to give up on them. “Believe in us again,” Wariner said. “We are clean. There’s a lot of clean athletes out there.”

Yet while this new generation may indeed be cleaner, they are paying for their forebears’ misdemeanours. A broad hope among these young stars is that the Graham trial will represent a final drawing of the line. As Wariner said: “I just hope it is done with after this.” Anyone with an affinity for the sport would share that hope, but it may prove a slim one. If the evidence in San Francisco does unmask another cast of drugs cheats, the lead-up to Beijing – and beyond – will be filled with recriminations, the redistribution of medals and the rewriting of history. Athletics these days is a sport in which medals are won and lost in court and it would be nice if, in China, we could revert to distributing them from a trackside podium.

Much may depend on the presiding judge, Susan Illston. Graham is charged with perjury – he faces up to 15 years in jail – and it is for her to decide how relevant is a new list of allegedly transgressing world champions. If she judges that names are appropriate, then both sides have declared that they have ammunition aplenty. Heredia is promising to bring down some of the sport’s greats. Graham said: “There’s going to be a lot of publicity on a lot of people’s parts who did a lot of things behind closed doors. It’s all going to be dragged out in front of the whole world. It’s going to embarrass the United States and it’s going to embarrass these athletes.”

Top of that list would seem to be Greene. It is one thing to be named in the press, but quite another if the allegation of serial cheating is made under oath. Greene’s legal representatives will thus be watching closely, asking themselves whether they have grounds for a lawsuit against Heredia for defamation. Heredia’s own credibility is questionable: a dope-pusher without an American passport, who could easily be slung out of the country, may be particularly keen to tell the prosecution what they want to hear.

And if, for instance, you are Greene and you are clean, what do you do? Go to court knowing how the headlines will play? Or take it on the chin? Either way, he appears to have suffered an irreparable blow. And if Greene’s name is contaminated, it asks questions of his former training partners, one of whom is Jon Drummond, who happens to be Gay’s coach. This, unfortunately, is the way the tentacles of suspicion spread when that element of trust is broken.

Drummond yesterday put as much distance as he could between himself and his old team. “As far as those guys’ lives go I don’t know what they’ve done since I left,” he said. “I don’t know what their lifestyles are. When I left, I cut ties. Everything I’ve read about our group is all speculation, it’s nothing I’ve seen or know or heard.” As he spoke, Drummond was being marshalled by three track and field press officers, such is the level of paranoia among the athletics community.

The problem for all, though, is that no amount of PR will be able to control the flow of information when the circus moves from the track to the courtroom today. It is Graham on trial in San Francisco, though it may as well be his entire sport.

Taking the Stand

Key witnesses in the Graham trial

Angel Heredia

Former discus thrower and self-proclaimed supplier of performance-enhancing drugs. Graham claims never to have met him; a photograph of the two together would appear to suggest otherwise.

Jeff Novitzky

Former investigator for US Internal Revenue Services. His work broke the Balco scandal.

Antonio Pettigrew

Now 40 and a coach at the University of North Carolina. Reputation had not been publicly questioned before his name appeared on the witness list for this trial. Won 400 metres gold at the 1991 World Championships.

Dennis Mitchell

41, gold medal-winner in one Olympic and two World Championships US sprint relay teams. Was banned for two years in 1998 after testing positive for testosterone. Is expected to say that Graham injected him with human growth hormone.