Jeff Burton had a momentary lapse of ignition. Dale Earnhardt Jr. had a momentary lapse of concentration. In each case, it was enough to ruin what could have been a top-five finish in Sunday's UAW-DaimlerChrysler 400 at Las Vegas Motor Speedway.

For Burton, it wrecked any chance of overtaking Mark Martin for the points lead. For Earnhardt, it took the shine off what could have been an even more impressive comeback after starting the day 40th in owner points.

Both drivers were impressive throughout Sunday's race. A hot day, combined with the new surface and hard tires, made for treacherous racing conditions, but Burton and Earnhardt were solid.

Earnhardt, who started 28th, gained track position by not pitting on Lap 17 when most of the field came in for service. He then stayed among the leaders for the rest of the day.

"The track was very slick and very rough, and I was just out there hangin' on and drivin' my [butt] off every lap," Earnhardt said. "I think everybody was.

"I saw some miraculous saves out there -- I mean world-class, top-10 unbelievable saves -- right in front of me. Guys that should have crashed every corner and didn't. The track was outta control because it's a new surface and it was hot and slick and nasty."

Burton, winner of Saturday's Busch Series race, seemingly had the car to beat until late in the event when his engine began to experience an electrical problem. Faced with a decision whether to replace the battery following a caution for Clint Bowyer's crash on Lap 225, Burton and crew chief Scott Miller opted for tires and fuel instead, hoping there'd be enough juice left to go the distance.

As Burton returned to the track second behind Jeff Gordon, the No. 8 crew got Earnhardt in and out of the pits within striking distance of the leaders.

Burton eventually regained the lead on Lap 235 following a stirring battle with eventual winner Jimmie Johnson and Gordon. However, at about the point where Johnson finally caught and passed Burton for good, the engine in the No. 31 Chevrolet bogged down again -- leaving Burton and Miller no choice but to hope for another yellow in order to switch out batteries.

It came on Lap 251 when Kasey Kahne met disaster in Turn 2. The pits were still closed on the following lap when Burton, knowing he had no choice in the matter, headed for his pit stall for repairs. Inexplicably, Junior -- running fifth at the time and directly behind Burton on the track -- followed suit as Carl Edwards, also planning on making another stop, was able to swerve back onto the track before reaching the commitment cone.

"I just followed the 31 car down pit lane because he was the lead-lap car right in front of us," Earnhardt said. "I forgot he was having some sort of engine trouble and needed to pit right then.

"I never saw the [pit lane] light or the flag. I was just focused on following him and didn't realize the pits were closed until it was too late."

Earnhardt realized his error almost immediately.

"I don't like making mistakes. I don't like having any part of 'em," Junior said. "But that was a mistake to come down pit lane.

"We were talking on the radio about staying out because there was less than 20 laps left, but there weren't that many cars on the lead lap. So [crew chief Tony Eury Jr.] said 'I'm thinkin' about pitting here and taking some tires,' so that's what I'm thinking in my mind. You have to make decisions like that to have a chance to win the race."

The bad news? Junior was forced to restart the race at the tail end of the lead-lap cars. The good news? Because of attrition, the No. 8 Chevrolet was only 13th when the green flag flew for the final time with 11 laps remaining.

With four fresh tires, Earnhardt was able to regain two positions before the checkered flag while Burton wound up 15th.

For the driver of the No. 8, Sunday's finish wasn't what it could have been. Still, it allowed Junior to vault 12 positions in points to a more respectable 28th with Atlanta on the horizon.

"I'm pleased overall. Anybody that leaves this weekend without a wrecked racecar should feel lucky," Earnhardt said. "I'm glad to get out of here with a decent finish and a car that could run in the top five.

"We still had a good car and we had some really superb pit stops. We all had to deal with the conditions, and it seemed like we could run with just about anybody on long runs."