Michael Andretti and Al Unser Jr. quit driving during the last two seasons.
Marco Andretti is 18 and has the weight of the American open-wheel world on his narrow shoulders.
On Sunday, winning in his first race in the Indy Racing League's developmental Infiniti Pro Series, the son of Michael Andretti and grandson of Mario Andretti caused a bigger stir among the sport's longtime fans than did the 1 through 4 sweep by his father's Andretti Green Racing team later that day in the IndyCar Series event at St. Petersburg, Fla.
Al Speyer, director of racing for Bridgestone/Firestone, which furnishes tires for both the IRL and rival Champ Car World Series, was as excited as anyone. Two days before the Infiniti Pro race, Speyer spoke of the hope for the future as he watched Marco and Alfred Unser, 22, son of Al Unser Jr., being interviewed.
"I think maybe this can cause a spark," Speyer said. "I'm thrilled this legacy and competition will continue."
Andretti and Unser are two of a handful of second- and third-generation drivers who may hold the future of American open-wheel racing in their hands, along with Arie Luyendyk Jr. and A.J. Foyt IV, grandson of A.J. Foyt Jr.
Those surnames captured the imagination -- and the wins and championships -- of the racing world for decades. They and a few others dominated the ovals and road courses of America until, slowly, they began to lose the edge and face the fact that it was time to retire.
Michael Andretti called it quits early in the 2003 season, and Al Unser Jr. stepped out of the cockpit midway through last year. That left the top level of the American open-wheel sport with only struggling third-generation driver Foyt IV to carry on the tradition of the famous names that led the sport through the 60s, 70s, 80s and 90s.
The decline of the sport was hastened in 1996 when the IRL came along as a rival to the established CART Series. It split the sport's fan base and started a war that has left both sides far behind NASCAR in fans, TV ratings and allure.
But both series have soldiered on, working hard to regain some of that lost momentum, even while lamenting that the top young drivers who might have made a difference -- names such as Jeff Gordon, Tony Stewart, Ryan Newman and Kasey Kahne -- have gone to NASCAR.
The current leaders in the IRL and Champ Car are either foreign drivers who can't seem to work their way into the hearts of mainstream U.S. race fans or virtually unknown Americans.
Enter this new cadre of youngsters, aching to follow in the footsteps of their famous fathers or grandfathers. The bloodlines are certainly there.
Marco's dad won a CART championship and is the leading race winner in that series. Mario Andretti won just about everything there is to win in the sport, including the Indianapolis 500, the Daytona 500, a Formula One championship and four Indy-car titles.
Alfred's father is a two-time CART champ and two-time Indy winner, while grandfather Al Unser is a four-time Indy winner. His uncle, Bobby Unser, also won three Indy 500s.
The elder Luyendyk won two Indy 500s, and Foyt is the grandson of four-time Indy winner A.J. Foyt Jr., who also won a Daytona 500 and the 24 Hours of Le Mans. He is the winningest driver in American open-wheel history.
"I've always been an Unser and Marco has always been an Andretti," Alfred said. "So the pressure's always been there. We just have to go out and do it."