updated 4:16 p.m. ET Sept. 5, 2005

FONTANA, Calif. - Kyle Busch became the youngest winner in NASCAR’s top series Sunday night, a feat that was almost an afterthought with most of the focus on the battle for the final spots in The Chase for the championship.

At the end of Sony HD 500, the bottom of the top 10 in the Nextel Cup point standings was shaken up, with Matt Kenseth and Jamie McMurray in and Ryan Newman and Jeff Gordon out with only one more race before the start of the 10-man, 10-race finale.

That didn’t bother the 20-year-old Busch, the brother of reigning Cup champion Kurt Busch, as he celebrated his breakthrough victory at California Speedway.

“It’s unbelievable,” said the rookie whose previous best finishes were seconds this year in Las Vegas and Dover. “We should have been here at least five times this year, but we haven’t been able to close the deal.”

The previous youngest winner was Donald Thomas, who was four days older than Busch when he won in Atlanta in November 1952.

FREE VIDEO 'I can't believe it' Sept. 4: Kyle Busch, 20, talks about becoming the youngest race winner in NASCAR history. NBC Sports

Driving a Chevrolet for Hendrick Motorsports, Busch led 95 laps on the way to the victory in his 31st career start.

Busch was leading on lap 240 when debris brought out the 10th of 11 cautions in the race. With the race scheduled to end on lap 250, Busch faked as if he was going to pit on lap 241 and, when all the other leaders followed, he went ahead and pitted.

His crew put on only two tires and Busch was able to beat everyone else back onto the track and hold the lead to the end.

“My nerves were getting to me,” Busch said. “When I made that last pit stop (under caution), everybody followed me in and I thought, ‘Cool, we’re going to be all right.’ That stop is what got us the win.”

While Busch took control late in the race that was extended to 254 laps because of a caution period, the battle within a battle was raging for positions in the standings.

Only the top 10 drivers in the points following Saturday night’s race at Richmond will be eligible to contend for the championship in the last 10 races of the season.

Greg Biffle, already solidly in The Chase, finished second, followed by Brian Vickers, Carl Edwards, series points leader Tony Stewart and Kasey Kahne. Vickers is Busch’s teammate.

Kenseth, coming off his first victory of the season last week in Bristol, had another strong race, finishing seventh. He has charged from 17th in the points following the Pocono race July 24.

“We’ve run much better and you know the guys that have been around us in the points have had some trouble and maybe haven’t run as well in the second half of the year,” said Kenseth, the 2003 series champion. “But we’re not in it, yet. We still have another week to go.”

Edwards solidified his spot in the top 10, remaining eighth and all but clinching a spot in The Chase, while Kenseth moved to ninth, 10 points ahead of McMurray, who is one point ahead of Newman and 30 in front of Gordon, who began the night in 10th.

Going into Richmond, only 62 points separate eighth-place Kenseth from 13th-place Elliott Sadler, who finished 17th after winning last year’s race.

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A crash on lap 247, involving Robby Gordon, Scott Riggs, Scott Wimmer, Jeff Burton and Sterling Marlin gave Biffle one last shot at Busch, but he was unable to challenge the youngster after the green flag waved for a two-lap shootout on lap 253 — three laps after the scheduled finish.

“Kyle got a great restart,” Biffle said. “Great job by those guys tonight. They deserve it.”

Jeff Gordon, who struggled throughout the race, appeared to finally get back into contention when he got into the top 10 late in the event. But a handling problem sent the three-time California winner reeling from 10th on a restart on lap 216 to a 21st-place finish.

“It’s just one of those nights,” he said. “It was pathetic. We’ll go to Richmond and see what we can do. It doesn’t matter right now (where we race). Everywhere we go, we either stink or we’re good. Apparently what we’ve done in the past doesn’t mean anything right now.”

Newman also was disappointed with his 18th-place finish.

“We’re still alive now,” Newman said. “We’ve got our heads just barely below water. We’ve got a chance to come up for a breath of fresh air.”

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