Daytona Beach, FL (Sports Network) - Kevin Harvick held off Tony Stewart and Greg Biffle on the last lap to win Saturday night's Sprint Unlimited at Daytona International Speedway, a race that marked the competition debut of NASCAR's new Generation-6 car.

Harvick grabbed the lead when he came off of pit road first following a mandatory four-tire pit stop after the first segment, which was 30 laps in length, had concluded. He dominated from there, leading 40 of the remaining 45 laps.

Stewart, who led the way at the completion of the first segment, challenged Harvick for the lead on the backstretch during the 75th and final lap, but Harvick blocked Stewart from a pass. That allowed Biffle to advance on the high side of the track. But Harvick was able to outrun Biffle and then beat him to the finish line by 0.149 seconds.

"It's a good way to start off Speedweeks," said Harvick, who won the exhibition race at Daytona for the third time in last five years.

This is a lame-duck season for Harvick, as he is leaving Richard Childress Racing at the end of the year and moving over to Stewart-Haas Racing for the 2014 season.

"I just think it's one of those deals where, for us, it's really about winning races," he noted. "The politics are one thing, but when we get to the racetrack, it's about sitting in this race car and making it as fast as it will go. Those guys (No. 29 RCR team) don't care about anything but winning, and they want to do good."

Harvick joined Stewart and Dale Jarrett as three-time winners of this race, which kicks off Speedweeks at Daytona. Dale Earnhardt is the all-time leader in wins for the preseason event with six. Harvick also gave team owner Richard Childress his eighth win in this race.

Just 12 drivers finished this event, as a multi-car wreck occurred on lap 15. Stewart dove down the track and clipped Marcos Ambrose in turn three. Stewart managed to save his car, but Jimmie Johnson, who was running on the outside at the time, lost control and spun out, which triggered the incident in turn two.

"I got a big run on the 20 (Matt Kenseth), and I went to the bottom, thinking that I was clear," Stewart said. "The spotter did not clear me, so I went on my own. I thought I had enough of a run to be clear of the third-place guy (Ambrose). I made a move for the lead and probably was a little anxious too early."

Nine drivers were involved in the accident. Johnson, Jeff Gordon, Kurt Busch, Kyle Busch, who won this race last year, Mark Martin and Denny Hamlin had their night at Daytona end early.

"It's really unfortunate and wished we could have been around a lot longer to learn some more things and see what could transpire later in the race," Kyle Busch said.

Despite Sprint Cup Series teams testing the Gen-6 for three days at Daytona last month, there were some unknowns about the new car heading into this race. In the opening minutes of Friday's practice session at Daytona, Kenseth made contact with Kurt Busch coming out of turn four, which created a five-car accident. Edwards, Martin and Juan Pablo Montoya were forced to backup cars.

"Gosh, we didn't get very far along there, did we?" Martin said after the accident early in the Sprint Unlimited.

Joey Logano, who made his first start in Penske Racing's No. 22 Ford, finished third. Stewart took the fourth spot, while Kenseth, making his debut in Joe Gibbs Racing's No. 20 Toyota, completed the top-five.

Sixth through 10th were: Aric Almirola, Kasey Kahne, Dale Earnhardt Jr., Martin Truex Jr. and Montoya.

The starting lineup was not determined until shortly before the start of the race. Fans who attended the event at Daytona voted the lineup based on when drivers earned their pole position during the 2012 Sprint Cup season (Daytona 500 first place - final race of the season at Homestead-Miami Speedway last place). Since Edwards won the pole for last year's Daytona 500, he was credited with the pole, but Edwards had to start from the rear of the field due to switching to a backup car.