Greg Biffle led the first Saturday practice for the Sprint Cup Auto Club 400 at Auto Club Speedway.
He ran a fast lap of 186.253 mph in the No. 16 Ford Fusion. No. 51 AJ Allmendinger, No. 18 Kyle Busch, No. 11 Denny Hamlin and No. 78 Kurt Busch rounded out the rest of the top five on the speed chart for this practice. Timmy Hill in the No. 33 was the slowest. Biffle qualified second for the race but changed the engine after yesterday's practice. The No. 16 will have to drop to the rear of the field at the green flag.