Dennis Mitchell must have thought he had the tricky business done with when it came to the Sydney Olympics. Having convinced some of the blazers that too much sex and too much drink had caused him to test positive a couple of years back, he must have felt all the karma was good and all the gods were conspiring with him. He won the 1999 US championships and set his face towards Australia. Not to be.

He served some suspension time anyway and had his 1999 season voided, but he came back in May talking big. On Saturday in Sacramento, in the early evening sun, a large crowd gathered in the alley behind the college track to watch him suffer. He had just finished eighth - last - in the 100 metres final.

Mitchell, still wearing the vivid lime outfit which apparently makes him the "green machine", was leaning with his back against a Portaloo, his woman massaging his chest, his cellphone tacked to his ear and his salty tears running down his cheeks. People just gathered and looked until the chest massage stopped and the masseuse whipped around and asked, "What y'all starin' at?"

She looked like the sort of gal who could make a guy test positive and we were tempted to make a merry comment to that effect. Instead, somebody chirped up, "Welcome to the trials, Dennis", and then we moved along. Welcome to the US Olympic Trials. Welcome to the real world. The Yanks insist that this quadrennial bloodbath is the greatest track meet on earth, and for drama and cataclysmic loss it is indeed hard to beat. You finish top three or you watch the Olympics on the telly like the rest of us. Oh the weeping, oh the gnashing of teeth!

The graveyard of the US Olympic Trials is filled with distinguished headstones. Maurice Greene in 1996, Dan O'Brien in 1992 and so on back to poor old Harrison Dillard, who won 82 straight hurdles races before the 1948 trials and then - well, you guessed it. That's the beauty of the trials: there is no next week, no next year, no second chance, no appeals, no resting on past achievements.

This is the 21st time the trials have been staged, but those happenings have produced 55 world records and a million tears. Already this weekend the carcasses of some pretty big warriors lay strewn about the field. Gail Devers, defending Olympic champion, dumped out of the 100 metres by younger, faster models. John Godina, silver medallist in the shot put in Atlanta, will be doing some gardening in September unless he can pull something out in next Saturday's discus final. No glimpse of a reprieve for Jeff Hartwig, who broke the US pole vaulting record a month ago and then failed to qualify for Sydney this weekend.

And the week is just beginning. Showtime has yet happen. While Dennis Mitchell mourned himself in the sunshine, Maurice Greene was celebrating himself in the shade of the media tent.

"I am Olympian! I am Olympian! I am Olympian!" he roared as he came and left, having won the 100 metres final on Saturday evening. In between times he gave a riproaring, virtuoso performance press conference, a sweet and loud paean to himself, his manifest glories and his pending whupping of Michael Johnson's ass when the two of them "get it on" next weekend.

This weekend the guys were just taking care of business, Johnson breezing imperiously through the 400 metres heats, Greene recovering from a bad month on the European circuit and a gammy start in Saturday's final to win the race in 10.01 seconds. That left them with plenty of time to consider next weekend's festival of ego when the pair clash in the 200 metres, the first time they have met since Greene beat Johnson in 1998.

Greene has been letting his tongue run faster than his legs in Sacramento. "If people call Johnson Superman," says Mo-Reece, "well I'm Kryptonite."

Johnson, playing the rigid elder statesman card, is not amused. "Maurice isn't mature enough because he hasn't been in the sport long enough to know that bragging isn't going to make him feel better."

If the boys are cutting up rough, it's scarcely any sweeter among the women. Marion Jones has been walking the high tightrope of braggadocio herself. Her "drive for five" campaign, announcing her intention to win five golds in Sydney, would be hubris enough for most, but she also stars in a series of Nike television adverts where, in the role of a DJ, she delivers little homilies while Me and Mrs Jones spins on the turntable. She dishes it on everything from education to women in sport. Sample:

"All right, suckers. Ears up. Minds open. Message from Mrs Jones . . .

"What if you had to fly overseas just to find people who knew you? That wouldn't be too cool.

"Yet that's how y'all treat Michael, Marion and Moh-reeece, the world's fastest humans.

"Track stars need more love, the more the better. Can you dig it?"

Well, Inger Miller hasn't been digging the Marion Jones love drive. Miller beat Jones in a schools race in California back in 1990 and was told immediately afterwards, "It's good that you beat her now because I don't think you'll ever beat her again."

So it has proved, and on Saturday the pattern continued with Miller being forced into second place in the 100 metres final. As if that wasn't bad enough, Miller and third-place finisher Chrystie Gaines were ushered off the track during their post-race lap of honour to clear the way for the great media caravan that was trotting backwards filming Marion Jones' lap of honour.

Miller gets to go head-to-head with Mrs Jones again next weekend when they compete in the 200 metres. Meantime there are big fish to fry. By then a key element of Jones "drive for five" may have been shaken loose. In the early hours of this morning she was putting her ungainly long jumping style to the test yet again in her weakest event, an event furthermore in which Dawn Burrell (sister of Leroy) is favourite and Jackie Joyner Kersee (childhood idol of Marion Jones) is back competing. Jones should have just about enough to get a top three place.

The women's 5000 metres could be another roughhouse occasion if disappointed refugees from last night's 1,500 metres final barrel their way into the field. Mark Carroll's partner, Amy Rudolph, will be among the favourites, but the field could be so heavy with big names that the results sheet will read like a casualty list.

Then there is the men's 110 metres hurdles final next Sunday, one of the stronger events for American track and field. Defending Olympic champion Allen Johnson is under pressure from 21-yearold whippersnapper Terrence Trammell and perennial contender Mark Crear. The field will have five of the world's top ten hurdlers in it.

The women's 100 metres hurdles final the same afternoon offers Gail Devers a chance for redemption in what has traditionally (despite the absence of Olympic medals) been her best event.

Eight days in the California sun, track and field's equivalent of the running of the bulls. The common sentiment among the track freaks is that if you can stand the heat at the US Olympic Trials you can stand anything. Some big names are about to put an amen to that.