WATKINS GLEN, N.Y. — If Kyle Busch has a weakness, it's apparently going to be awfully difficult to find.

After rivals Jimmie Johnson and Jeff Gordon said during the week they thought he was slipping following two straight lackluster finishes, Busch answered by making NASCAR history today. He led 52 laps from the pole and won the Centurion Boats at The Glen at Watkins Glen International to become the first driver in NASCAR's history to win three road course races in one season.

"That's pretty neat, pretty special to me," said Busch, who finished second Saturday in the Nationwide race here. "To be a force to be reckoned with means a lot. This year has just been phenomenal. It's just crazy."

Busch, who also clinched the top spot in the 10-race Chase for the Sprint Cup title, has won 16 races in NASCAR's top three series this season — eight in Sprint Cup, six in Nationwide and two in trucks. His win Sunday completed a trifecta on road courses that includes the Nationwide race in Mexico in April and the Cup race at Sonoma in June.

Busch also joined another select group. Only Jeff Gordon, Tony Stewart and Robby Gordon had swept both Cup road course events in the same year.

"That kid's awesome," said Steve Addington, Busch's crew chief. "I can't believe we don't win a race in three or four weeks and we're in a slump."

Actually, Busch has won four of the past seven races, and Sunday's victory gives him 80 bonus points for the Chase, 50 more than Carl Edwards with four races remaining before the postseason. Drivers get 10 bonus points for a victory.

After a 43-minute red-flag stoppage due to a multicar pileup with eight laps to go, Busch held off Joe Gibbs Racing teammate Stewart, who was bidding for his fifth win here in seven starts. Stewart settled for his second straight runner-up finish and moved within 10 points of Jeff Gordon for sixth in the standings.

"I never could get the runs in the right spots," said Stewart, who also has finished second twice here in the past three years. "I needed to stay with him to be close enough to try to make a move in a braking zone. We never could get close enough to get an opportunity."

Marcos Ambrose of Tasmania, who started last in the No. 21 Wood Brothers Ford, finished an amazing third a day after winning the Nationwide race.

"It's just a great weekend all around," Ambrose said after only his third Cup start of his brief NASCAR career. "I hope I can give the Wood Brothers a shot in the arm that they need to really get the momentum to move forward."

Ambrose was followed by Juan Pablo Montoya and Martin Truex Jr.

Kevin Harvick was sixth, followed by Jimmie Johnson, Denny Hamlin, Edwards and Kurt Busch. Matt Kenseth finished 12th to move into 12th place in the standings, 22 points ahead of Clint Bowyer in the race for the final slot to make the postseason.

Jeff Gordon, a four-time winner at Watkins Glen, began the day sixth in points, but faded quickly after a strong start and finished 29th.

Dale Earnhardt Jr., who has never won a Cup race on a road course, took off to a big lead after passing Busch on the second lap and figured to be a strong contender. But poor pit strategy derailed his effort and he finished 22nd after leading 33 laps and fell two slots in the standings to fourth.

Johnson had a stout car, too, but an unscheduled pit stop for a tire problem spoiled his chances of notching the first road-course victory of his career.

Running up front most of the day around the 2.45-mile, 11-turn course, Busch allowed Stewart to pass him on lap 54 so Stewart could collect five bonus points for leading, then quickly regained the top spot when Stewart moved over the next time around.

Busch and Stewart made their final pit stop one lap later and regained the top two spots on lap 65 when Earnhardt gave up the lead and pitted under caution, losing all of his track position.

"He was fast," Busch said of Stewart. "I knew that he was going to be good. We both came in together and left together, and that was probably the win right there, to be able to beat him off pit road. Once we did that, I kind of got up through the esses better than him and we pulled away."

The JGR teammates stayed 1-2 until Ryan Newman, running third and hoping for a strong finish to enhance his chances of making the Chase, slid off course in turn 1 on lap 79, bringing out the third caution of the race and bunching the field for a nine-lap dash to the finish.

The dash was shortlived. A stunning multicar crash on the final turn of lap 82 of the 220.5-mile race brought out a red flag stoppage that lasted 43 minutes.

The pileup started when Michael McDowell spun David Gilliland, who caromed off the wall and was slammed hard again by Bobby Labonte, with both cars spinning violently around. Max Papis, Dave Blaney, and Sam Hornish Jr. also were unable to avoid the carnage, with Hornish slamming hard into the water barrier at the entrance to pit road.

"I couldn't see," Blaney said. "It was a big hit for a bunch of guys."

Labonte was taken to a local hospital for evaluation and released. The other drivers involved were taken to the care center and also released.

"I'm fine, I'm broken in my heart," Papis said. "We were ready to attack. I know with nine to go, you get up on the wheel and push hard. Pushing and shoving is OK, but that was crazy. I guess there wasn't much place to go. They kept pushing and shoving."

The 90-lap race resumed with six laps remaining, and Busch sailed away on the restart and was never challenged.

"I was worried," Busch said. "I knew getting a good start was going to be good, and once I got that, then it changed all my worries."