Green–white–checker finish

In North American motorsport, a green–white–checker finish is one in which no yellow caution flag is shown during the final laps. Many race rules require a green–white–checker finish, because no competition may take place, including no passing, while a caution flag is showing. The name alludes to three racing flags:

The prescribed number of final laps is usually two, but may be as many as ten. If a caution flag is shown within that number of laps of the scheduled finish, then the number of remaining laps will not be decremented until the green flag is shown again. The exact provisions vary between organisations. For some years after 2007, NASCAR on Fox referred to the extra laps after the scheduled number as Overdrive, an allusion to the term overtime used in many other sports.

In the ARCA Racing Series, there is a two-stage version of the rule. The rules are arranged such that the checkered flag must wave under green flag conditions.

Such a format allows an unlimited number of attempts at a green flag finish. During the event at Gateway International Raceway on July 28, 2006, 22 laps (27.5 miles) were added to the 120-lap (150-mile) scheduled distance.

This version, or a similar variant with no green/white rule, is used in most short tracks.

The Camping World East and West Series used a rule similar to the ARCA rule with an unlimited number of attempts. In April 2005, two green-white-checkered attempts were used at Phoenix International Raceway for a Camping World West race.

The NASCAR Camping World truck Series adopted a green-white-checkered flag rule initially during nationally televised 200-lap exhibition races at Tucson Raceway Park in Arizona.

When the green flag is waved on the restart, there are two laps remaining in the race. If the yellow flag comes out at any time during the restart, each subsequent restart will be a two-lap restart. (From 1995 until mid-1998 and again since 2003, racing back to the caution was prohibited in the series.)

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