Johnson bounced back from a poor showing at last week's Daytona 500 to take his fifth Auto Club championship, aided by a late-race caution raised due to an accident involving Brad Keselowski.
Johnson was able to make his final pit stop just before the yellow flag was displayed for Keselowski's mishap and exited pit road before then race-leader Jeff Burton crossed the line to start the caution period. He went in front for good with 24 laps to go when Burton and the other leaders pitted for the last time.
Johnson has won the last three fall races at the Fontana track, which was the scene of his first Sprint Cup win during his 2002 rookie season.
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