Kyle Busch wins Xfinity race

Kyle Busch won for the 10th time in the Xfinity Series this season with a victory at Phoenix International Raceway on the night NASCAR’s second-tier series’ set its inaugural championship field.

The final four for next weekend’s race at Homestead-Miami Speedway will be a battle between Dale Earnhardt Jr. and Joe Gibbs.

Both car owners got two drivers each into the championship field the first year NASCAR rolled out the Chase for its lower two national series. The Chase uses the same elimination format as the Sprint Cup Series, and eight drivers were competing for the final four slots on Saturday night.

Daniel Suarez and Erik Jones, both driving for Joe Gibbs Racing, got in. JR Motorsports qualified Justin Allgaier and Elliott Sadler.

But, after the race, Sadler’s car was being inspected by NASCAR for an apparent loose lug nut on his car. It’s unclear if Sadler could face a points penalty that would knock him out of the championship field.

“I think we might have a loose lug. They’ll look at it. But, hey, we did what we had to do,” Sadler said.

Sadler, a longtime NASCAR veteran, is seeking his first title at the national level and has his best chance this year in this winner-take-all format.

“We’re pumped about it, we really put all our eggs in one basket, and that’s that Homestead car,” he said.

Allgaier had to stretch a drying gas tank over the closing laps to claim his spot and keep Blake Koch out of the field. Koch was keeping an eye post-race on Sadler’s situation, but immediately apologized for an earlier incident with Darrell Wallace Jr. that knocked Wallace out of title contention.