Greg Biffle led the second practice for the Sprint Cup Kobalt Tools 400 at Las Vegas Motor Speedway.
He ran a fast lap of 189.427 mph in the No. 16 Ford Fusion. No. 48 Jimmie Johnson, No. 55 Mark Martin, No. 99 Carl Edwards and No. 29 Kevin Harvick rounded out the rest of the top 5 on the speed chart for this practice. Michael McDowell in the No. 98 was the slowest of the 43 cars out on the track.