Putting his reputation on the line and risking embarrassment in front of 40,000 fans and a seven-digit TV audience, NASCAR Sprint Cup star Kurt Busch competed in the highly competitive Pro Stock class at the NHRA Gatornationals, one of the biggest events in drag racing.

When it was over, Busch hadn't won – he didn't even win a round – but he demonstrated beyond a doubt that he can drive a Pro Stock car and that, with a little experience, he could win.

In a rented Dodge Avenger prepared by an all-volunteer crew working alongside Pro Stock vet Allen Johnson's J&J Racing team, the 2004 NASCAR Sprint Cup champion lost in the opening round of Pro Stock eliminations – but not by much. By that point, he'd already accomplished his stated goal: he qualified. There are no provisionals in drag racing; if you don't qualify on Friday or Saturday, you don't race on Sunday.

“Drag racing takes a whole different kind of focus,” says Busch, whose daily drive is the No. 22 Penske Racing Shell Dodge in the Sprint Cup. “In Cup racing, you can feel race time getting closer, and it's a four-hour marathon, so you keep yourself at a level that you know you can maintain. Here, you never know exactly when you're going to run. You know what the schedule is, but there can always be delays from the cars in front of you. Then all of a sudden, it's time to go, and you have to perform.

“When you finally do get up there, you'd better get everything out of that car. It's, ‘Do it right, and do it right now,' because you only get one chance. In NASCAR, if you miss your line a little, you have 499 more chances to get it right!”

Busch's first qualifying attempt was a disappointing 19sec shutoff run – not that he did anything wrong. His Shell-backed Avenger shook violently as soon as he dumped the clutch; there was nothing he could have done. “But then I made my first mistake,” he adds. “I should have eased back into the throttle so that at least I'd have the best e.t. of all the drivers who had to shut off, and I'd have run farther back in the next session.”

In that next session, Busch did something that's likely never happened in the 41-year history of Pro Stock: Instead of focusing on the staged lights at the top of the Tree, he cranked his head 90 degrees to the right and stared at the other driver, waiting for him to roll in first. There he was, a 22-time winner in America's biggest racing series, but he didn't know one of the first rules of his new sport: never take your eye off the Tree.

“I committed the cardinal sin,” says Busch, who possessed exactly one race of prior drag racing experience – last year's Gatornationals, where he competed in a sportsman division called Super Gas. “It was a rookie mistake. I looked over at Vince [Nobile]'s car, just like I would in NASCAR. I was thinking, ‘Man, are you ever going to stage?' Then I looked back at the Tree, saw that he was already in, and I knew right then that I was done.”

Busch's run was disqualified – he didn't even get a time. Now under even more intense scrutiny, he laid down a solid 6.53 at 211mph Saturday morning that guaranteed his place in the field. On his final qualifying attempt, in lesser conditions that afternoon, he managed a consistent 6.55. “On the 6.53, I missed the 1-2 shift a little – it comes really fast – and on the 6.55, I put the motor on the rev-limiter chip before the other guy even staged,” he says. “But Sunday morning in eliminations,  I made the best run I've ever made.”

With every eye in the place on him, Busch had a respectable .049sec reaction time (.043 is average), nailed all four shifts, and nearly matched his qualifying numbers with a 6.541 in the dreaded left lane. It was enough to have beaten half the drivers in the field, but not, as it turned out, the driver in the other lane. Opponent Erica Enders came up with the best reaction time of the entire round (.021) and outran him by .003sec for a car-length win.

“He did an outstanding job,” Enders says, “and I mean outstanding. To go from nowhere to being competitive in your first race is harder than anyone can imagine. Pro Stocks are hard to drive – a lot harder than all the people who are here to see Top Fuel and Funny Car would ever believe. He almost beat me, and there was a lot of pressure on both of us. I could say I didn't know it was Kurt Busch over there, but I knew. How could I not? That was one of the biggest round wins of my career.”

Busch's mentor, Allen Johnson, a perennial Pro Stock title contender, was equally impressed. “What can I say? The guy is a natural. It's not easy to drive one of these cars, and it's definitely not easy to drive one right, and for the experience he had, I thought he did an excellent job.”

Says Busch: “I'm still trying to teach myself to think differently, to look at every run like it's a perfect run just waiting to happen. Allen's crew chief, Mark Ingersoll, and his whole team bent over backward to help me, and all the guys on my team had the car set up perfectly. Anything you do wrong as a driver – leave late, miss a shift point even a little, or steer the car around too much – adds thousandths or hundredths of a second to that perfect run.

“The most difficult part of the drag strip is the first 100 feet. Staging properly is absolutely crucial, and second gear comes up fast. So does third. It's just a whole different mindset. At the start line, you have your right foot to the wood, a 1,400hp engine, and a car that's not going anywhere until you release the line-loc [which locks the brakes on] and the clutch. It pulls 3G off the line, and reaching 210mph in that short of a distance is a lot of fun, but the first few times I did this, I thought, ‘I'm in way over my head here. Do I really have this thing under control?'”

Long before he headed to the Gatornationals, Busch had made runs under the watchful eye of legendary instructor Roy Hill, who has been driving Pro Stock cars since the class's inception in the 1970s. Busch then rented a Dodge from the Mountain View Tire team to race alongside Johnson's experienced Mopar team. Drivers throughout the Pro Stock pits loved the exposure that Busch's presence brought to the class.

“Drag racers are a great fraternity of drivers,” Busch says. “Those guys are first class. I can't believe how they embraced me. I guess I was kind of a big fish there, and everything I did was under a microscope, but it was a warm, welcome feeling to have so many drivers – not just Pro Stock, but guys in other pro classes, too – pulling for me to qualify.

“It's nothing like the Cup series. No one is going to do anything to make it easier on you, and they're not letting you into their little clique. But you have so much track time there, so many sessions to prove yourself. In drag racing, you get one shot – and you'd better get it right.”

• For the full version of this feature article, plus much more, check out the May 2011 issue of RACER magazine. CLICK HERE to subscribe.