Updated

Championship contender Matt Kenseth posted the fastest speed during final practice for NASCAR's season finale.

One major problem: points leader Jimmie Johnson was fast, too. Johnson had the second-quickest lap around Homestead-Miami Speedway on Saturday and had the fastest 10-lap average.

Kenseth reached 171.980 mph around the 1½-mile oval, just ahead of Johnson's 171.647. Defending series champion Brad Keselowski was third, followed by Martin Truex Jr. and Kevin Harvick.

The 10-lap average is often a better indicator of the top cars. Johnson averaged 167.905 mph over his first 10 practice laps.

Johnson, Kenseth and Harvick are the only drivers still in contention for the title. Johnson enters Sunday's finale with a 28-point lead over Kenseth. Johnson needs to finish 23rd or better to win his sixth title in eight years.