Dale Earnhardt, who had what was described as a "blackout" during last Sunday's Southern 500 and wrecked on the first lap, underwent tests yesterday at a North Carolina hospital for a third consecutive day and his status is in doubt for Saturday night's race in Richmond, according to his spokesman and NASCAR officials.

Earnhardt, 46, spent Sunday night at the McLeod Medical Center in Florence, S.C., for observation before being released Monday morning. Earnhardt has since undergone tests at two hospitals in North Carolina, producing no conclusive results for his "blackout," according to Earnhardt's spokesman, David Allen.

Richard Childress, who owns the cars Earnhardt drives, said Earnhardt spent much of yesterday undergoing tests at the Bowman-Gray School of Medicine in Winston-Salem, N.C. Childress said Earnhardt stopped at the Welcome, N.C., race shop after leaving the hospital and Earnhardt said he felt fine.

However, NASCAR officials were awaiting results of those tests from doctors before deciding whether they will permit Earnhardt to drive in Saturday's Exide NASCAR Select Batteries 400 at Richmond International Raceway. They hope to decide today.

Earnhardt was not available to comment yesterday. He was scheduled to appear at a NASCAR news conference yesterday in Minneapolis, but he did not attend.

Allen said Earnhardt has undergone tests for respiratory, circulatory, substance, body chemical, heat, carbon monoxide and stress problems all three days. He said barring any changes, Earnhardt will not undergo any more tests.

"He has always had the persona and image of a tough guy -- now he has a human ailment and it is hard for us to deal with," said Allen, who has represented Earnhardt since 1981. "It sure is baffling everyone. We would like to know and have something to point at. The unknown is a lot harder to deal with than the known."

One NASCAR official said drivers are required to undergo a physical examination prior to the season-opening Daytona 500. The only other time drivers must receive medical clearance is after a crash or illness, and Earnhardt received such clearance after being involved in a bad crash at Daytona in February. He was not seriously hurt.

"We are not doctors -- we need somebody to tell us he is ready to go," said NASCAR spokesman Kevin Triplett. "As soon as they do that, he can go race. We are waiting to have further conversations with the doctors."

NASCAR does not have its own doctors. The sanctioning body treats drivers as independent contractors, a NASCAR official said.

Earnhardt, known for his penchant to take naps at unusual times in unusual locations, apparently fell asleep in his car in the moments before last Sunday's race at Darlington (S.C.) Raceway. However, the seven-time Winston Cup champion awoke and began the race in normal fashion, driving a handful of warmup laps before crashing in Turns 1 and 2 on the first lap of the race. He reportedly told a crew member, "I'm sorry, I saw two racetracks."

"He doesn't remember since he got in the car until they got him to the hospital," Dale Earnhardt Jr. said.

"He was perfectly normal until three minutes before the race," Childress said. "It concerns me a lot because he is one of my best friends."

Earnhardt has started 537 consecutive races, the second-longest streak in the Winston Cup series behind Terry Labonte's streak of 560 races. However, he is in the midst of the longest winless stretch of his career, having gone 51 races since winning the Purolator 500 in Hampton, Ga., on March 10, 1996.

If Earnhardt is cleared to race, he is scheduled to fly to Richmond tonight and stay in his motor home at the racetrack. Practice begins Friday morning for Saturday night's race.

If Earnhardt cannot race, Childress said he and crew chief Larry McReynolds have discussed alternate plans. If Earnhardt is sidelined for a brief period of time, Childress could hire a driver for this weekend -- possibly Steve Park, who drives a Busch Grand National car owned by Earnhardt and is scheduled to drive a Winston Cup car for Earnhardt next season. If Earnhardt is unable to race for a longer period, a different driver may be substituted.

"I am concerned because he is a great part of the sport, he is one of the people who hold the sport together," said Ray Evernham, crew chief for the car driven by Jeff Gordon. "I concerned for him as a friend and for his health. He is someone everyone wants to be like, so you just hope he is all right." CAPTION: Dale Earnhardt's medical tests have proved inconclusive ever since he crashed in Sunday's Southern 500. He reportedly said: "I'm sorry, I saw two racetracks."