INDIANAPOLIS • Mario Andretti sees the same spark in Fernando Alonso that drove him to take on all comers around the world and said the Spaniard is a threat to win the Indianapolis 500.

Alonso set the motor racing world abuzz last month when he said he had been granted clearance by his McLaren Formula One team to miss the Monaco Grand Prix and race in the 101st Indy 500 on May 28 in pursuit of the sport's famed Triple Crown - a Formula One title and Indy 500 and Le Mans wins.

While the late Graham Hill is the only driver to achieve the feat, Andretti also stands alone as the only driver to win an F1 race, an Indy500 and Daytona 500.

"I embraced the challenges, that's why I did it, because I was curious," said the American.

"Some drivers are very happy specialising. I wasn't. I see the same spark in Alonso. I know how he feels because this was always my challenge, to go into somebody else's sandbox and see if I could win at their own game. There's nothing better than that."

Alonso, 35, underwent IndyCar's rookie orientation programme on Wednesday to get used to the 4km Brickyard course.

"It was fun," he said. "Everything looks good. Now it's time to start the real thing."

McLaren will enter the race with a Honda-engined Indy car run by Andretti Autosport, owned by former McLaren driver Michael Andretti, who put together a detailed game plan for Alonso that began in a simulator.

REUTERS, AGENCE FRANCE-PRESSE