Reigning NASCAR Sprint Cup champion Kyle Busch looked to have clinched pole position for this weekend's Folds of Honor QuikTrip 500 at Atlanta Motor Speedway in qualifying on Friday evening.

However his qualifying time was subsequently disallowed after the #18 failed post-qualifying inspection over a problem with the rear of the car, meaning that the 30-year-old will now have to start the race from the back of the 39-car field

The Joe Gibbs Racing driver had posted a lap of 28.925s (191.668mph) at the 1.54-mile (2.48 km) quad-oval track, narrowly pipping his older brother Kurt - himself a former Cup champion - by just 0.013s. It would have been the third time that Kyle and Kurt would have started 1-2, the first occasion being at their home track in Las Vegas in March 2009 while the second was as Texas in April 2013, with Kyle going on to win both races.

Instead, Kyle's disqualification means that Kurt was subsequently promoted to pole position, his 20th pole position in 542 NASCAR Sprint Cup Series starts. His last pole position was at Pocono last June when he went on to finish in fifth place. It's the first time in 25 visits to Atlanta that Kurt has succeeded in capturing the pole.

"It's an awesome run that the car had in it. The team did a good job to dial it in for the three rounds," said Kurt. "I was just trying to make sure I didn't slip a tire any extra. It's really easy to overdrive Atlanta Motor Speedway. The track challenges the driver, the car and the tires. It's a fun place to come and try to lay down a lap.

"Overall with the way the developments came up from tech inspection this shows the amount of enforcement that NASCAR is ready to imply to their technical procedures on what a car has to do to comply to all specs," the driver of the Stewart-Haas Racing #41 added.

Originally thinking that he had qualified in third place, Chip Ganassi Racing's Jamie McMurray will now start alongside Kurt Busch up on the front row having posted a final round qualifying lap which was 0.221s off the pole time.

"It's interesting because I ran the bottom here last time," commented McMurray. "I kind of expected to run the bottom in qualifying this time. It seemed like everybody ran higher in 1 and 2, which I think will be a good sign for the race because the bottom will work as well. I'm hoping that the new rules package maybe plays into that, I don't know."

Roush Fenway Racing's Trevor Bayne qualified fourth and is promoted to third on the grid. His previous best starting position at Atlanta was 29th last year, and the only time he's started higher on the grid was in the autumn race at Daytona in 2011. Richard Childress Racing's Ryan Newman takes fourth spot on the grid alongside him.

"I was hoping for a top-15 day," beamed Bayne. "That's what we're working towards and that's our goal every week - to run to top-15 until we can run top ten every week and be consistent and don't make mistakes. This is a pleasant surprise, for sure.

"Atlanta is where you see what you've really got," he continued. "Obviously, we hope that translates to race speed. It's not just one lap speed, we have to make our cars last and not wear our front tyres. That's kind of my concern right now, but there's been a lot of effort put into this and I'm really proud of my guys. This feels a lot like a win."

"Our guys did a good job of adapting the car to qualifying trim," said Newman. "I think this is pretty equal as to where we qualified last spring so that's a good indication of good preparation in the offseason. I think race trim is going to be super-exciting for us as drivers. I hope the fans can enjoy [the new low-downforce aero package]. You're putting the driver back into the equation, which is part of what we were missing in my opinion."

Bayne's team mate Ricky Stenhouse Jr. is paired with SHR's Kevin Harvick on row three, while JGR's Carl Edwards, RCR's Austin Dillon, Furniture Row Racing's Martin Truex Jr. and Richard Petty Motorsport's Brian Scott complete the top ten. The final driver who made it into the final round of qualifying was Hendrick Motorsport's Kasey Kahne, who will now start from 11th place on the grid following Kyle Busch's disqualification.

Notable drivers missing out on the pole shootout included Daytona 500 winner Denny Hamlin and his JGR team mate Matt Kenseth who will start from 12th and 13th places respectively on Sunday afternoon. Dale Earnhardt Jr. (Hendrick) lines up in 16th, Brad Keselowski (Penske) in 17th and Jimmie Johnson (Hendrick) in 19th. CGR's Kyle Larson was only able to manage 20th despite topping the sole Friday practice session earlier in the day.

Among those who failed to even progress from the first round were Daytona 500 pole winner Chase Elliott (Hendrick), Joey Logano (Penske) and Danica Patrick (SHR).

"It was close," shrugged Elliott, who will start from 24th place on the grid. "We needed to be a little bit faster than that to contend for the top 12 anyway, so we're just off a little bit from what we were hoping for. But the good news is it's a long race on Sunday and we have another day of practice tomorrow, so we'll try to get things a little better."

"We were just really loose," commented Logano. "I don't really understand. We weren't super-fast in practice, but we were a top-10 car for sure. We were really, really loose the first run and made some changes, but it's hard to go fast here the second run when tyres wear out so much.

"We did go a little faster, but that one kind of hurts. We've got to figure it out. We've got a little bit of work to do. It's obviously a new package and we apparently don't have our heads wrapped around it perfectly yet, but we'll get it. We've just got to keep our heads down and keep digging. It's still a long weekend here."

Full qualifying and Friday practice times from Atlanta

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