Lucky Dog

The Lucky Dog rule is a motorsport regulation that allows the first car running one lap behind the race leader to regain that lost lap during a yellow flag caution period.

When a caution flag comes out during a race, all cars must slow down and follow a pace car around the track. During this time, race officials identify which driver is running in first place among cars that are one lap down. This driver becomes the "lucky dog" and gets a free pass to rejoin the lead lap.

The lucky dog driver must drive past the pace car and position themselves at the back of the group of lead lap cars. Once the race restarts with a green flag, they're back on the same lap as the leaders, giving them a fresh chance to compete for the win.

This rule exists primarily for safety and competition reasons. Before the Lucky Dog rule, drivers would often speed dangerously to reach the start/finish line before the caution took effect, hoping to gain a lap. The rule eliminates this risky behavior while keeping more cars competitive in the race.

NASCAR introduced the Lucky Dog rule in 2003, where it's also called the "free pass" or "beneficiary rule." Other racing series like IndyCar use similar systems. The rule has made races more exciting by keeping more drivers in contention for victories.

However, not every lapped driver can become the lucky dog. Drivers who caused the caution that triggered the rule are typically ineligible. Cars with serious mechanical problems or those penalized for dangerous driving may also be excluded from receiving the free pass.

While some racing purists argue the Lucky Dog rule gives undeserved advantages to slower cars, most fans and drivers appreciate how it creates more competitive racing and reduces dangerous driving during caution periods.