By MIKE HARRIS Herald correspondent

Known as "The Intimidator" or "Old Ironhead," Dale Earnhardt was tough and unyielding - a winner on the circuit and often sarcastic and calculating off it.

He had a reputation as a driver never afraid to bang into cars around him or shake his fist at a rival.

Despite those traits, or perhaps because of them, Earnhardt was a key figure in the explosive growth of Nascar (the National Association for Stock Car Racing) during the past 20 years from a regional sport into the mainstream.

Nascar attracted a big following and provided the opportunity for drivers to be among the world's best sports earners - Earnhardt's success brought him more than $US40 million ($93 million).

That is what made his death in Monday's Daytona 500 so shocking.

"This is incredible, just incredible," fellow driver Jeremy Mayfield said. "You figure he'll bounce right back.

"Your first thought is, 'Hey, he'll probably come back next week at Rockingham and beat us all'."

As word of the fatal, last-lap accident spread, many among the 195,000-strong crowd cried and the flag in the middle of Daytona International Speedway's vast infield waved at half-mast.

The death of Earnhardt, still a championship contender at 49, was the biggest blow to motor racing since the 1994 crash that killed the former Formula One world champion Ayrton Senna.

Most forms of motor racing have strong followings, but just as saloon-car series can attract bigger crowds than Formula One, so Nascar, with its familiar Chevrolets, Pontiacs and Fords, captures the imagination of millions in the US and around the world, appealing to basic driving and competitive instincts.

Out on the oval track, drivers are pushing what looks like your car to its limit at speeds of up to 320 km/h on what, with a little imagination, could just be a piece of the public highway.

Earnhardt built up the sport on the track, winning the Winston Cup for Nascar champion seven times.

But on the day when the sport began a new era with the return of Dodge after 16 years and the beginning of a six-year $US2.8 billion TV contract, its biggest draw was gone.

Daytona Beach is the home of Nascar, having staged the first race sanctioned by the fledgling organisation in 1948. Earnhardt was the first driver killed in the Daytona 500, which began in 1959.

He died perhaps because of an uncharacteristic decision to let his son, the newest driver on his own team, fight it out for victory while he protected the team position from challengers.

Earnhardt crashed on the last turn of the last lap vying for third place at the front of a tight five-car pack.

In front of him, Michael Waltrip held off Dale Earnhardt jun for what should have been the biggest moment in the short history of the Earnhardt team.

Earnhardt had to be cut from his battered car, and in hospital was pronounced dead of head injuries.

Rescue staff had tried to save him at the track but a doctor described Earnhardt as having "life-ending type injuries at the time of impact and nothing could be done for him."

Earnhardt's death was a stunning blow for Nascar after a season in which three of its best young drivers were killed in separate accidents.

Adam Petty, the fourth generation of stock car racing's most famous family, and Kenny Irwin died in crashes two months apart. Tony Roper died after a crash during a truck race.

All three died of the same type of head injuries that killed Earnhardt.

Since those deaths, safety has become a big issue. There has been debate over possible rules changes and the use of new safety equipment.

Earnhardt wore an old style open-faced helmet and shunned some of Nascar's other basic safety innovations.

He did not like the restrictor plates Nascar used to slow speeds at its fastest tracks, where he was a master. He also refused to wear a head and neck brace that had been touted as a way to help prevent serious head injuries.

But medical officers at the accident did not think that those devices would necessarily have helped Earnhardt.

As the three-times Winston Cup winner, Jeff Gordon said: "It's great racing, it's exciting, there's a lot of passing, a lot of lead changes. But one little mistake and something like that is going to happen. It's inevitable."

- INDEPENDENT