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While Jimmie Johnson claimed his record eighth win at Dover International Speedway, Dale Earnhardt Jr. felt discouraged after finishing second in Sunday's AAA 400.

Earnhardt had a solid performance at Dover -- the third race in the Chase for the Sprint Cup championship. He won the pole with a new track qualifying record there on Friday. Earnhardt ran in front for a total of 80 laps, which is the most laps he's led in an event this year. But a pit-road mistake in the early going probably cost him an opportunity to win his first race of the season.

During a round of green-flag stops, Earnhardt overshot the commitment line for pit road and was forced to make another lap around before coming in for service. He was leading the way prior to his stop but dropped to eighth.

"I take responsibility for getting a little too eager coming onto pit road for that green flag stop," Earnhardt said. "We were lucky we didn't have more trouble through that whole deal. I didn't know what the heck the rules are for that, so I was figuring we got off pretty light."

Earnhardt encountered another problem on pit road late in the race when he was caught up behind the slower car of Mark Martin. It cost him more track position.

The fourth and final caution with less than 30 laps to go set up the last round of pit stops. Earnhardt made a four-tire change, while his Hendrick Motorsports teammate, Johnson, took just two tires. Johnson came out of the pits first while Earnhardt exited in fourth.

After the restart with 26 laps left, Earnhardt quickly charged to second and chased down Johnson for the lead. But Johnson held off Earnhardt at the finish by a half second to surpass Bobby Allison and Richard Petty for most career wins at Dover.

Earnhardt finished in the runner-up spot for the third time this season.

"I'll be honest with you, it sucks to lose regardless of who wins," he said. "It's probably harder to run second than it is fifth or 10th. When you have a car like we had (Sunday), you don't get good cars every week, you like to capitalize.

"It doesn't bother me that it was Jimmie. I know Jimmie is going to be good here. Plus he's my teammate. I want to see him do well. When he does well, it indirectly affects us and benefits us."

Johnson, the five-time Sprint Cup Series champion, put on a dominating performance by leading 243 of 400 laps. With the win, Johnson trimmed Matt Kenseth's lead in the Chase standings to eight points. Kenseth finished seventh after winning the first two races in the playoffs -- Chicagoland and New Hampshire.

"I ran my guts out to stay ahead of (Earnhardt)," Johnson said. "Any switch I could flip in the car that was a fan that might help the car turn my brake bias, everything and anything I could twist, turn, pull, push, I did, then just drove the (expletive) out of that thing. I was able to keep him at bay for 10, 12 laps. At that point I was able to stretch a little bit and get back to running a smart race."

With seven races remaining in the Chase, Earnhardt sits 10th in the standings. He trails Kenseth by 57 points. Earnhardt finished 35th at Chicagoland after suffering engine failure late in the event but rebounded at New Hampshire with a sixth-place run.

"I feel like in the last couple of weeks, we've been able to really show what our team's capable of," Earnhardt said. "We've been really quick on the sheet every day, fast in practice. The changes we're making, everything seems to be working right, going in the direction you want. I feel like when we get it right, we can compete and we can win."

Earnhardt has not won a race since June 2012 at Michigan (48 races ago). While a Sprint Cup championship might be a tall order for him this year, a race win wouldn't be. Earnhardt recently said he would be disappointed if his team did not score a victory this season.

The next Chase race is Sunday at Kansas. Earnhardt did not compete in last year's fall events at Charlotte and Kansas due to a concussion he sustained during an accident at Talladega.