HUNTLY, New Zealand -- Tiger Woods hunkered behind the wheel of his stock car, its motor coughing noisily. The world's most recognizable sportsman was suddenly unrecognizable under a flame-retardant racesuit, helmet and tinted visor.

A faint movement of his gloved hands and a drumming of the fingers on the steering wheel gave the only sign of apprehension ahead of this, his first venture into dirt-track auto racing.

The green flag fell, the rear wheels of his car churned, then found traction and he surged forward into a fume of exhaust smoke, rain and mud. Chaos ensued.

Cars cannoned into each other and into the low concrete wall that rings the circuit, spitting sparks. A heavy rain shower made the track slick, almost too hazardous to allow racing to continue, and Woods' car, black and orange under a huge aerofoil, was almost unmanageable.

He leaned forward to stare closely through the grill that is the driver's window, gripped the wheel more tightly and pushed down harder on the accelerator. Suddenly Woods is the man known to millions for his calm and dignified presence on the world's golf courses.

In the second of two celebrity races organized by his caddie Steve Williams to raise money for Williams' charitable foundation which benefits disadvantaged youth, Woods forced his way from the back of the grid to the front.

He took the lead on the sixth of 12 laps over a 400-meter dirt oval in undulating farmland outside this small coal mining town, and, despite a detour into the wall which left his car sparking and tires smoking, he held on to win.

In the first race, Woods was not so lucky. He started on the outside of the front row, quickly slipped back through the field and, in this mad form of auto racing in which cars are used as weapons, acted as a "blocker" for his team.

There are two five-man teams and, when not a front-runner, Woods' job is prevent rivals from passing. He took to the task with relish, and a disturbing abandon.

Early in the first race, Woods swung the wheel and his car slews sideways to make contact with an overtaking competitor, sending the rival's car skidding into the grassy infield. Tiger wrestled for control, bringing his own car back on course just as it is rear-ended by another vehicle.

He spins, sits motionless momentarily, then takes advantage of a clear track to rejoin the race among a melee of cars.

This is team stock-car racing, the only branch of motorsport in which collisions are not only legal but encouraged. The first car over the line is the winner and that's all that matters.

It's also competition and for Woods that's business as usual. His competitive instinct kicks in and he becomes determined he won't be passed.

Woods is driving a modified stock car, a vehicle made especially for the rough and tumble of dirt track racing. He sits in a fiberglass cab on top of a standard chassis surrounded by heavy iron jousting bars, most parts likely salvaged from local junkyards.

His car manages 400 horsepower from a 1300 c.c. engine which pushes him around the narrow oval at more than 80kph (50mph), often in a barely controlled slide.

Woods captained one of two teams. The other is captained by Tana Umaga, the former captain of the All Blacks rugby team who holds pole position for the first of two races. Each team has a complement of dirt track specialists and specialist auto racers.

They relish their work.

Woods enters into the spirit of the event before the race saying "if they knock me off, I'll knock them off" and he's as good as his word.

His jostles with Umaga from the flag and narrowly misses the outside wall. He crashes sideways into an opposing car, locks bumpers then bounces clear.

Nothing could be further from golf and yet Woods employs many of its principles. His driving is aggressive but accurate, he tries to avoid the rough with some success, his engine gives him a few short putts and he keeps his nerve in a close finish.

One of the world's most valuable and marketable sportsmen put himself through the symphony of grating crashes just a day after making the world's highest tourist bungy jump. It endears him to the 7,000 speedway fans - the petrolheads - who have come from around New Zealand to see him.

"No branch of motor racing is entirely safe," says speedway vice president Nigel Wilson. "But for all drivers including Tiger, we try to make it as safe as possible. He has all the safety equipment we can provide... belts and bar and neck braces.

"I'll tell you what. He's a whole light safer on that track than he is out on the highway coming here."

Woods had no second thoughts about accepting Williams' challenge to drive here.

"I'm just so excited to be here," he says in greeting the crowd Monday. "Stevie (Williams) puts his heart and soul into this sport and when Stevie asks me to do something, I'm there in a heartbeat."

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