How NASCAR overtime works for Autotrader 400 in Atlanta

The Autotrader 400 is going to finish in thrilling fashion.

It's overtime at the former Atlanta Motor Speedway.

The OT format creates great drama, but it comes after a delay. The race is in a red flag after a William Byron-prompted crash late in the race.

There were about less than 10 laps to go when the crash happened. The laps ran out by then, and the track had to be cleared, so the cars all stopped and waited.

How does NASCAR overtime work?

NASCAR overtime is two laps.

It starts with the green flag. That prompts one lap.

Then there's the white flag, signaling the final lap.

The checkered flag signals the winner.

As long as it gets to the white flag without another caution, it finishes on the checkered, no matter how many crashes happen on that final lap.

If a crash happens on the first lap of overtime, it goes to another caution, and they'll try the green-white-checkered again.

It should be fun.

Bubba Wallace is leading when it resumes.

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