Ryan Newman thought his solid eighth-place finish in Sunday's Bojangles' Southern 500 at Darlington Raceway put him in pretty good shape to make a late run at the Chase for the Sprint Cup playoffs.

Now he can't be too sure.

The cars of both Newman and Kyle Larson, who finished third, failed post-race laser inspection following Sunday's race. Larson is locked into the Chase by virtue of his recent victory at Michigan, but Newman is trying to get in on points and any resulting penalties could jeopardize that with just one race remaining this Saturday at Richmond International Raceway before the 16-driver Chase field is set.

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Any penalties will be announced this week, likely on Tuesday but certainly no later than Wednesday.

Newman is fighting for a Chase berth and is seven points out of the final transfer spot heading to Richmond this weekend. The Richard Childress Racing driver lost 10 points earlier this year after Atlanta when he and his teammates were penalized after NASCAR confiscated the braces in the right-rear corners of their cars.

Newman's car was chosen as randomly for Sunday's post-race inspection.

Newman's No. 31 RCR Chevrolet will be examined further at the NASCAR Reserch and Development Center in Concord, North Carolina, as will the cars of race winner Martin Truex Jr. and second-place finisher Kevin Harvick.

Truex and Harvick's cars both passed at-track inspection after the race.