DOVER — Jimmie Johnson had reached the moment of truth.

After working his way through the field all afternoon, he’d finally made it to the front row.

But as the veteran driver went to put his car in gear on a restart with about 46 laps left in Sunday’s AAA 400 Drive for Autism, nothing happened.

“As soon as I went from second and tried to go to third ... it didn’t even go to third,” Johnson explained later. “It stopped before it ever went to third. And then I tried fourth and third, then fourth. ... there was a long pause there where I thought I missed a shift. But it wouldn’t go in gear.”

That simple mechanical issue set off a chain-reaction pileup that totally changed Sunday’s Sprint Cup race at Dover International Speedway in an instant.

Johnson’s inability to get his car going on the restart caused many of the cars behind him to plow into each other. Eventually 18 cars were involved in the wreck — one short of the Monster Mile record.

While some of those cars did return to the track, the accident knocked a slew of contenders out of contention.

Martin Truex Jr. may have been as frustrated as any driver.

A week ago, he led 172 laps at Kansas before being derailed by a wheel problem. On Sunday, after leading 47 laps, he was directly behind Johnson on the restart.

Truex not only slammed into Johnson’s car but he was then hit from behind by Kevin Harvick. Ironically, Truex allowed Carl Edwards to beat him out of pit road just before the restart so he could line up on the outside — behind Johnson.

“I don’t know when it’s going to end,” Truex said about his run of bad luck. “All I can worry about is what we’re doing. Our guys did a really god job today.

“When we needed to be the best car, I thought we were. It was just one of those deals — in the wrong place at the wrong time. It’s frustrating but we got a top 10 out of it so that’s not too bad.

“I just hate that it happened,” he added. “I wanted to be fourth on that restart but I didn’t want to be fourth that bad. I should have been third.”

Johnson, who was going after his 11th Dover victory, credited Truex for being patient in the situation.

“He gave me a couple opportunities to try to find a gear,” said Johnson.

Then there was Harvick. He led a total of 117 laps — 32 more than anybody else.

But he was hurt by slow pit stops even before the big pileup. The Sprint Cup points leader ended up only 15th in Sunday’s race.

Joey Logano only led two laps in the race but he was running near the front when the wreck occurred. He finished 22nd.

Asked if he saw what happened, Logano answered, “That was the problem, we couldn’t see.”

“When you are stacked up on the restart like that, there isn’t much to be able to see at all,” he said. “I tried checking up and going to the bottom like we were going to miss it and got hit from behind. That sent me into it more. Now we need a new radiator.

“We have been the victim of circumstances the last few weeks. It is what it is. I am not going to say it was bad luck. ... We weren’t the fastest car but we were a top-five car for sure. Things happen.”

Greg Biffle was one of three drivers who didn’t return to the track after the accident. He had to settle for a 29th-place finish.

“I just saw cars stopped in front of me and there was just no way we could stop,” said Biffle. “The spotter was telling me to go low, which I am not sure if that was the right move either. I don’t know if there is anything I could have done.”

Of course, Johnson paid a price for his car’s malfunction, too.

He did lead four laps, reaching 3,000 laps led at Dover for his career. Only seven drivers in Sprint Cup history have reached that milestone at one track.

But Johnson finished 25th after the pileup. After 13 top-10 finishes in a 15-race span at Dover, he has now finished just 41st and 25th in his last two races on the Monster Mile.

“In my career I’ve never had a transmission do that to me,” said Johnson. “The ‘no gear available’ is something I’ve never had before. I lost a shot at winning and I hate to see all those cars torn up.”