Saturday night's NASCAR Sprint All-Star Race at Lowe's Motor Speedway isn't rocket science, but it's not your ordinary race, either.

It is run in four segments, rather than one, and there's even a twist to the pit stops.

When asked if he understood the format, ten-time all-star Tony Stewart said. "Nope, but I'm sure it won't be hard to figure out."

He did know the length, though.

"I know that it's a no-holds-barred 100 laps," he said, "and you could swear that we're short-track racing on a big mile-and-a-half track."

The first segment is 50 laps, followed by two 20-lap segments and a ten-lap shootout. Only green-flag laps count in the final segment.

During the first segment, there is a mandatory green-flag stop at lap 25. And teams can't do a gas-and-go. To emphasise the team aspect of the sport, a four-tyre change is mandatory.

The caution flag will be thrown at the end of the first two segments, and pit stops are optional. There will be a ten-minute break between the third and final segments. Regular adjustments can be made during each of these pit stops.

"It doesn't matter to me what they do with the format. Whatever it is, the goal is still to win it," said Stewart, whose best finish was second in 1999, his rookie year. "So, whether it's ten laps, 40 laps -- it doesn't matter to us. The important thing is that it puts on a good show for our fans. At the same time, you'll figure it out."

Although this is a non-points race, a lot is on the line--more than a million dollars goes to the winning team.

"I thought winning Talladega was awesome," said Brad Keselowski, who qualified for the all-star race with his surprise victory last month in the Aaron's 499, "but when I found out I would be in the all-star event...I mean, who wouldn't want the chance to race for a million dollars?"

The field will consist of 21 drivers. Here's the breakdown:

- Race winners since the start of the 2008 season (16): Ryan Newman, Carl Edwards, Kyle Busch, Jeff Burton, Denny Hamlin, Jimmie Johnson, Clint Bowyer, Kasey Kahne, Dale Earnhardt Jr., Kurt Busch, Greg Biffle, Matt Kenseth, Jeff Gordon, Mark Martin, Stewart and Keselowski.

- Drivers who have won an all-star race in the past ten years: Kevin Harvick.

- Sprint Cup champions in the past ten years: Bobby Labonte.

The other three will be determined Saturday night, two from the 40-lap Sprint Showdown that precedes the Sprint All-Star Race and one by fan vote.

The Sprint Showdown is two 20-lap segments, with the top two finishers transferring to the all-star race. The winner of the fan vote, from the remaining drivers, also transfers as long as his car is in "race-able condition", as determined by NASCAR.

Last year's all-star winner was Kasey Kahne, who finished fifth in the preliminary event but won the fan vote. AJ Allmendinger and Sam Hornish Jr. finished 1-2 to advance.

by Bill Marx/Sporting News