FORT WORTH, Texas -- Jimmie Johnson took a giant step toward his sixth NASCAR Sprint Cup championship by dominating Sunday's AAA Texas 500 at Texas Motor Speedway.
Johnson led 255 of the 334 laps to win his sixth race of the season and his first on a mile-and-a-half track this season.
Johnson now leads Matt Kenseth by seven points with only two races left in the season.
Kenseth had to battle back from a pit-road speeding penalty on lap 173 to finish fourth behind Johnson, Dale Earnhardt Jr. and Joey Logano.
The only problem Johnson had all afternoon came on lap 240 when his pit crew had trouble on the right-front tire. The long pit stop dropped Johnson to fifth.
But 16 laps later, Johnson was back out in front and was never headed as he cruised to the victory.
Kasey Kahne finished fifth, followed by Brad Keselowski, Denny Hamlin, Kevin Harvick, Clint Bowyer and Ryan Newman.
Kyle Busch was running third when he made his final pit stop of the race on lap 298. But he, too, was charged with speeding on pit road. As a result, he ended the 500-mile race in 13th place. Busch began the day in fifth place in the points standings.
Jeff Gordon began the race in third place in the standings, 27 points back of Johnson and Kenseth, who were tied for the top spot. But Gordon's championship hopes were wiped out on lap 73 when a left-front tire went flat, sending him hard into the wall. Gordon finished 38th.
Pole-sitter Carl Edwards had his victory hopes erased on lap 188 when he suffered engine failure. He finished 37th.