D A Y T O N A B E A C H, Fla., Feb. 19, 2001 -- Dale Earnhardt, one of the greatest drivers in auto racing history, died Sunday from injuries suffered in a last-lap crash at the Daytona 500.

An autopsy performed today to determine the exact cause of death, revealed Earnhardt died of blunt force trauma to the head, officials in Florida's Volusia County said, adding that they will treat the death as a "motor vehicle accident."

The 49-year-old stock car legend was traveling 180 mph, when his car was tapped from behind, turned around and sent head-on into a wall, only moments before his teammate Michael Waltrip and his son Dale Earnhardt Jr. finished the race in first and second places. In this final lap, Earnhardt was actually holding back by blocking the pack of cars behind him to give his son Dale, Jr. a chance to win the race. That's when Ken Schrader broadsided Earnhardt's car.

Doctor: Earnhardt Died Instantly

Rescuers attempted CPR while Earnhardt was pinned in his car. One of the first doctors on the scene said he believed Earnhardt died instantly.He never regained consciousness after the crash.

"I could tell, it broke my heart what was going happening," said track physician Dr. Steve Bohannon.

"I watched my hero die," says Pat Polysen, who was aboard a rescue and recovery team truck that rushed to the scene Sunday.

Earnhardt was cut free from his vehicle and transported to Halifax Medical Center with his son Dale, Jr. by his side. Earnhardt was pronounced dead soon after arrival, Dr. Steve Bohannon said.

"This is undoubtedly one of the toughest announcements that I've ever had to personally make," said NASCAR president Mike Helton, "but after the accident in turn four at the Daytona 500 we've lost Dale Earnhardt."

NASCAR chairman Bill France spoke during a news conference in Daytona Beach today and said he "couldn't think of a time that has been more tough in NASCAR history."

"He was a dear friend and he really liked the sport," France said. "Dale built NASCAR to what it is today. He will be a part of the sport for many generations to come."

In an emotional moment during the press conference, Waltrip, said that as he passed the finish line he was thinking about getting a big congratulatory hug from Earnhardt. "He would have come up and given me that big hug," Waltrip said. "But it was apparent to me then that in the twinkle of an eye you are in the presence of the Lord."

‘The Intimidator’ Behind the Wheel; A Thoughtful Friend Off the Track

Earnhardt — nicknamed "The Intimidator" — was known for his aggressive, hard-charging driving style, but off the track, friends and fans described him as thoughtful and generous.

"No one more was respected and loved by other race drivers — those in racing and fans — than Dale Earnhardt," said ESPN NASCAR commentator Ed Dubrow.

"He will be missed and we don't have to wait for history to know that he was one of the greatest."

The seven-time Winston Cup champion had won the Daytona 500 in 1998, in his 20th appearance in the event. With a total of 76 Winston Cup victories, including 34 on the Daytona track, Earnhardt was most active driver on the circuit.

Other drivers marveled at Earnhardt's uncanny ability to position himself behind other cars, using them to cut through the wind and make his vehicle more aerodynamic.

Earnhart was one of the major figures in transforming stock car racing from a regional sport to the huge television spectacle it is today.

Earnhardt is survived by his wife and four children, including his son Dale Jr.

‘Auto Racing’s Michael Jordan’

"We have lost our Michael Jordan, our Tiger Woods, and it's been a terrible day, it's left a black hole in this sport that we won't see filled for a long time," said H.A. "Humpy" Wheeler, president of Lowes Motor Speedway in Charlotte, N.C., and a longtime friend of Earnhardt.

Earnhardt's family was centered around auto racing. His father Ralph Earnhardt was a champion on small-track races, but never achieved success in higher-profile events such as NASCAR races.

Jerry Punch, a racing analyst for ESPN, said Earnhardt was protecting his teammates when the fatal accident occurred.

"He stayed there and ran a 180-185 mph screen," Punch noted.

Earnhardt was trying to block another driver, Sterling Marlin, from gaining on his teammates Earnhardt Jr. and Waltrip.

Marlin's car bumped his Chevrolet and set it spinning into the wall, where it was broadsided by Ken Schrader.

Accident Fuels Debate Over Safety

There have been two other fatalities from similar accidents around turns, raising concerns about a possible systematic problem.

The Lowes Motor Speedway installed a form of foam on the turn walls to try to prevent similar accidents.

Sunday's fatal crash is the biggest blow to the sport since Ayrton Senna, a three-time Formula One champion, died at Italy's San Marino Grand Prix in 1994.

NASCAR drivers Neil Bonnet and Rodney Orr were also killed in separate crashes in 1994, both while practicing for the Daytona 500.

Earnhardt himself had crashed at Daytona in 1997, flipping his vehicle but emerging without serious injury.

Too Much to Bear

For a racing community still healing from the loss of Adam Petty, the death of Dale Earnhardt was almost too much to bear.

Hours after the tragic event, a steady stream of devastated fans stopped at his race shop to mourn.

Jeff Goddard, an employee of Petty Enterprises, was one of them. Wearing a bright red Petty jacket, Goddard paced in front of the makeshift memorial created along the gate at DEI Inc.

“I just got in my car and drove and ended up here,” he said. “We kind of just got over the death of Adam, and now this. It’s devastating”

Petty, 19, was killed in a crash during practice at New Hampshire International Speedway last May. A fourth-generation driver, his death rocked the racing community. But it did little to brace anyone for the death of Earnhardt.

“No matter where it happens or how it happens or even how prepared you think you might be for it, losing somebody close to you hurts,” said Kyle Petty, Adam’s father.

ABCNEWS.com's Oliver Libaw and ABCNEWS Radio's Ed Dubrow and ABCNEWS' Ron Claiborne contributed to this report.