AVONDALE, Ariz. -- Matt Kenseth turned a two-tire stop into his fifth victory of the season, while Mark Martin edged closer to Tony Stewart in the battle for the Winston Cup championship.

Kenseth got out of the pits first after the leaders pitted on lap 261 of the 312-lap Checker Auto Parts 500K, and stayed out front the rest of the way Sunday at Phoenix International Speedway.

Stewart and Martin ran in the top 10 through most of the 500-kilometer race. Martin's fourth-place finish, combined with Stewart's eighth place, chopped the margin from 112 to 89 points with only next Sunday's race in Homestead, Fla., remaining.

''We made some adjustments on our last stop and the car just wasn't right,'' Stewart said. ''We didn't get hurt too much today. Now, we're going to a track I really like.''

No matter what Martin does next week, Stewart will win the title if he doesn't lead a lap and finishes 22nd or better, leads one lap and finishes 24th or better, or leads the most laps and finishes 25th or better.

Rusty Wallace finished second, Jeff Gordon finished third, followed by Martin, Dale Earnhardt Jr., Busch and Stewart.