Chase Elliott becomes NASCAR’s youngest champion at 18

Chase Elliott, 18, smiles as he celebrates his NASCAR Nationwide Championship with his father Bill Elliott, right, after finishing fifth at the NASCAR Nationwide Series auto race at Phoenix International Raceway, Saturday, Nov. 8, 2014, in Avondale, Ariz. AP

AVONDALE, Arizona — Chase Elliott has become the youngest champion in NASCAR history by wrapping up the Nationwide Series title Saturday at Phoenix International Raceway.

The 18-year-old rookie is the youngest driver to win a title in any of NASCAR’s three national series.

He clinched the championship for JR Motorsports with a fifth-place finish at Phoenix. His official celebration will have to wait until next week’s season finale at Homestead-Miami Speedway.

Brad Keselowski won the race with a pass of Kyle Busch following a restart on the two-lap overtime sprint to the finish. Busch led 187 of the 206 laps but was denied the victory because Keselowski was given the final chance to catch him after a caution with one lap remaining in regulation.