Dale Earnhardt Jr., who won the pole for the Daytona 500, will have to start in the rear of the field because of a crash that destroyed his primary car Wednesday in practice at Daytona International Speedway.

Earnhardt Jr. will also start at the rear of the field in the first Gatorade Duel qualifying race Thursday.

"The first thing I'd be worried about starting in the back is just not finding a good partner, getting lapped early – losing the draft is real easy to do sometimes if you don't get good starts," Earnhardt Jr. said.

The Hendrick Motorsports driver was collected in an accident as he was pushing Jimmie Johnson in a two-car draft in front of Martin Truex Jr., who was getting a push from Brian Vickers in another two-car draft. The two tandems came up on three slower cars – driven by Robby Gordon, David Gilliland and Michael Waltrip – that moved up the track. Johnson and Earnhardt Jr. checked up, causing Truex Jr. to hit Earnhardt Jr. in the rear and send both drivers spinning.

“We were coming around [turns] 3 and 4 and some guys on the inside moved up into the top lane, toward the top lane and me and Jimmie checked up because we didn’t know if they were coming into our lane and we got run over from behind,” Earnhardt Jr. said.

“It’s a tough deal. It’s the same old stuff that happens here. … They moved up in front of us and we lifted and the guys behind us didn’t know what was going on.”

Johnson, the five-time defending Cup champion, was able to keep his car from spinning and didn’t suffer damage but parked his car for the rest of the practice.

“Closing speed is high, but we’re all able to look in the mirror and pay attention to what’s going on,” Johnson said. “That was so avoidable. That didn’t need to happen. … I don’t know if they just didn’t know we were coming. It seems to me it was an innocent thing, but you can’t start on the bottom of the race track and then climb your way all the way to the top in the corners.”

Truex Jr. also had to go to a backup car but will only go to the rear of the field for his qualifying race because, unlike Earnhardt Jr., he has not secured his starting position yet – that will be done in the qualifying race.

“The guy behind you can’t see what’s going on,” Truex Jr. said. “When I talked to Brian, he had no idea that they were even checking up. I saw them kind of wiggling around and getting out of shape and I tried to save it, but the guy pushing is pushing fast and the next think you now, we’re spinning.”

Earnhardt Jr. didn’t even want to practice Wednesday. He now will race the Hendrick Motorsports car Jeff Gordon drove to an eighth-palce finish at Talladega last October.

The Budweiser Shootout car he wrecked Saturday is being repaired and will be his backup car for the rest of the week.

“I had a pole-sitting race car – I didn’t need to practice,” Earnhardt Jr. said. “I had a fast car and I didn’t want to practice it.”

But Earnhardt Jr. said he needs to race the backup car Thursday.

"We definitely want to run and see where the clearnces is [to the ground], make sure our clearances are good, make sure we don't have leaks and that good stuff," Earnhardt Jr. said. "[Hendrick officials] will sit down and say, 'This is the plan,' and I will get the plan and I will do whatever the plan is."

Kyle Busch was fastest in the first of two Sprint Cup practice sessions Wednesday with a speed of 200.254 mph. Greg Biffle was second at 200.249. Earnhardt Jr. had the third-fastest speed before the wreck followed by Johnson, Tony Stewart, Juan Pablo Montoya, AJ Allmendinger, Mark Martin, Kevin Harvick and Paul Menard.

NASCAR made a rules change earlier in the day, reducing the size of the holes in the restrictor plate in an effort to slow speeds and break up the two-car drafts. Drivers still ran in two-car packs throughout most of the practice session.

"The odds of us wrecking in that qualifying race probably are better than us winning it, especially starting in the back with a car that got no track time," Earnhardt Jr. said. "The odds of winning just went [worse] and the odds of wrecking just got better because we're starting in the back.

"I'll do whatever they say. If they say, 'Go for the trophy,' we'll go for the trophy. We have another race car after this. … It doesn't matter what kind of car you've got with this kind of drafting. The 22 [of Kurt Busch] wasn't a good car, he'll even admit it, and he won the [Budweiser] Shootout."