Kyle captured the Checker Auto Parts 500 after Kurt Busch was disciplined by his team.
AVONDALE, Ariz. -- It's a family thing.
Even as Kyle Busch celebrated victory at Phoenix on Sunday, he stood up for older brother Kurt, who was suspended by his team earlier in the day for a Friday night run-in with police.
"I just want to say I'm behind my brother 100 percent," the 20-year-old said after standing on top of his No. 5 Chevrolet and waving to the cheering crowd at Phoenix International Raceway.
Kurt Busch, the reigning Cup champion, was set down by Roush Racing earlier in the day for the final two races of the season because of a Friday night run-in with police.
Chase leader Tony Stewart finished in fourth, and now holds a 52-point lead over Jimmie Johnson, who finished seventh. Stewart also has an 87-point cushion over Carl Edwards, who came into the race with two straight victories but finished sixth Sunday.
Kyle Busch was able to put aside his feelings long enough to win a race in which he had to battle back from a lap down and then outrace veteran and title contender Greg Biffle for his second Cup victory in 41 starts.
"You just try to put all that stuff aside and deal with it another time," the youngster said. "This isn't the area for all that stuff. ... Just being out here to perform my best is what I'm here to do week in and week out and there shouldn't be any kind of distractions.
"Whether or not you're on the rocks with your girlfriend or you're doing whatever else outside the racetrack, you come in here and get in that race car, you're focused and you're down to one duty, and that's obviously to win the race."
Kurt Busch was suspended by his team after police accused him of reckless driving. Officers said he smelled of alcohol and was belligerent during a traffic stop near the speedway; he has denied that alcohol was involved.
Referring to his brother's victory here in April, Kyle said, "It is a pleasure to carry on the Busch family's name for both races this year."
The younger Busch defended his brother, saying, "Usually, things in the media are false and that's just what it comes down to sometimes."
When he was questioned about what he meant by that statement, Busch said, "I'm not going there, bud." He then walked out of the winner's press conference. But he returned about 20 minutes later and made a quiet statement before answering more questions about the race.
"There is a lot of speculation out in the media," he said. "And the only things that are out there to acknowledge is the police report and any information Kurt Busch chooses to release in the future."
Unlike his younger brother, Kurt Busch made the 10-man Chase for the championship but was running in eighth, virtually eliminated from a shot at winning another title. Kenny Wallace filled in for the Roush team and finished 16th.
Biffle's Roush Racing Ford dominated the race, leading 189 of the 312 laps in the Checker Auto Parts 500. But the younger Busch, who drives for Hendrick Motorsports, used a pit stop strategy to get track position, taking the lead for the first time on lap 230 by staying out when the leaders pitted.
Biffle, who pitted, had slipped all the way to 13th for the ensuing restart. The Roush driver sliced through traffic and eventually caught and passed Busch on lap 280. But the youngster wouldn't give up, challenging the veteran and regaining the lead for good on lap 285 with a strong inside move on the mile oval.
"I knew if I could pressure him a few more laps I could probably heat up his right rear a little more and we could get by him," Busch said. "My stuff was pretty well worn out there at the end and I'm sure his was too."
Biffle, who needed a strong showing to hang onto at least a chance to win the title, was not disappointed with his runner-up finish that left him in fourth place, 102 points behind Stewart with only next Sunday's Ford 400 at Homestead-Miami Speedway remaining.
"That is what we needed to do -- it's championship form right here," he said. "We wanted to win, but we came here and led a lot of laps and ran real strong and finished second. It just goes to show how solid this race team is."
He praised the Busch brothers, saying, "Both of those guys have a wonderful amount of talent and driving ability.
Busch went down a lap around the midpoint after pitting with a vibration, but got it back on a caution several laps later.
"It's neat for Kyle to win," Biffle said. Then, asked about Kurt's suspension, he added, "I think you'd have sympathy for anybody if you put yourself in that situation and got taken out of the race car. But I have absolutely no information about what was going on."
Busch, who also won at California Speedway in September, said he enjoyed the battle with Biffle.
"He had an awesome race car out there," Busch said. "I want to thank him for racing me clean the whole time. That was great. I had a blast racing with him. That was fun."
The suspension and the strong finish by the younger Busch took some of the spotlight away from the battle for the title, with Stewart finishing behind four-time champion Jeff Gordon.
"It's a big weekend for us next weekend," Stewart said. "I'm glad I've got a lot of stuff to do this week, shooting a commercial Tuesday in Charlotte and the I think the whole team is going to go fishing."
Edwards, a 26-year-old in his first full season in Cup, said he was satisfied with his performance, but disappointed not to gain more on Stewart.
"We have to go to Homestead with an aggressive mind-set," he said. "We can't go there and be conservative."