Clint Boyer led the first practice for the Sprint Cup Auto Club 400 at Auto Club Speedway.
His lap of 185.414 mph in the No. 15 Toyota Camry was the quickest of the 43 cars out on the track for the first practice session. No. 11 Denny Hamlin, No. 51 AJ Allmendinger, No. 18 Kyle Busch and No. 22 Joey Logano were the rest of the top five on the speed chart. No. 87 Joe Nemechek was the slowest.