Sprint Cup points leader Jeff Gordon cut short his practice Saturday because of back spasms and the No. 24 team has Regan Smith on standby should the four-time champion not be able to run the Coca-Cola 600.

Gordon went just 11 laps before he told his crew he couldn't continue. He left out of a side door of his hauler and was escorted out of the track to get treatment. Crew chief Alan Gustafson said the team would not run the car in the final practice session Saturday and instead get it ready for Sunday's race.

Gustafson said the plan was for Gordon to start the longest event in NASCAR. Should the pain be too much for the 42-year-old Gordon, Smith would take over the Hendrick Motorsports car.

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