NASCAR driver Kyle Larson ruled out of Sunday's Sprint Cup race at Martinsville after fainting

FILE - In this Feb. 13, 2015, file photo, driver Kyle Larson stands in the garage during a practice session for a NASCAR Sprint Cup Series auto race at Daytona International Speedway in Daytona Beach, Fla. Larson will not race at Martinsville Speedway on Sunday, March 29, 2015,failing to get medical clearance after fainting during an autograph session. The team said in a statement Sunday that Larson remains at Carolina's Medical Center in Charlotte, North Carolina, for more testing. (AP Photo/Terry Renna, File) (The Associated Press)

Sprint Cup driver Regan Smith talks to the media outside the hauler of driver Kyle Larson prior to the start of the NASCAR Sprint Cup race at the Martinsville Speedway in Martinsville, Va., Sunday, March 29, 2015. Smith is replacing Larson in the 42 car after Larson failed to get medical clearance after fainting during an autograph session. (AP Photo/Don Petersen) (The Associated Press)

NASCAR driver Kyle Larson will not race at Martinsville Speedway on Sunday, failing to get medical clearance after fainting during an autograph session.

The team said in a statement Sunday that Larson remains at Carolina's Medical Center in Charlotte, North Carolina, for more testing.

Regan Smith will replace Larson in the No. 42 Chevrolet at Martinsville.

The 2014 Sprint Cup rookie of the year and a budding star, Larson was initially checked out at Martinsville Memorial Hospital on Saturday after fainting at the Chevy Stage in the fan area, but doctors believed he should see a neurologist to be safe. So he flew back to Charlotte.

The team says, "Although all tests came back negative and Larson feels completely fine, the doctors felt he should be held for more testing."