Matt Kenseth led the first practice for the Sprint Cup Kobalt Tools 400 at Las Vegas Motor Speedway.
His lap of 187.396 mph in the No. 20 Toyota was the quickest of the 42 cars out on the track for the first practice session. No. 99 Carl Edwards, No. 29 Kevin Harvick, No. 56 Martin Truex Jr. and No. 88 Dale Earnhardt Jr. were the rest of the top five on the speed chart. No. 83 David Reutimann was the slowest.