INDIANAPOLIS (AP) – Marco Andretti is a fast learner.

The 18-year-old IRL rookie completed his first test session as an IndyCar Series driver and impressed his father, Michael, and grandfather, Mario, with his rapid progress.

Now he’s got two months to prepare for his debut race at Homestead-Miami Speedway. He recently tested for two days in Florida on the Sebring International Raceway’s 1.6-mile road course.

“Everything was a bit of an unknown to me until I got into the car, but now the questions are starting to be answered,” Andretti. “In that regard, it was good to finally get some time in the ArcaEx car.”

The Homestead-Miami 300 is scheduled for March 26.

“Overall, I’m very happy with his performance, as is the whole team,” Michael Andretti said. Last season, Marco won three of six races in the IRL’s developmental Infiniti Pro Series. On the road course at the Indianapolis Motor Speedway, he led from start to finish, increased his lead on almost each lap and was running so far out in front at the end that he was nearly alone on the track.

Indianapolis 500 and IRL champion Dan Wheldon left Andretti Green Racing for Ganassi Racing at the end of the season, and last month Michael Andretti gave his son a full-time ride with veteran teammates Tony Kanaan, Dario Franchitti and Bryan Herta. The 43-year-old team owner, who retired as a driver in 2003, said he would return to the cockpit for one more try at Indianapolis in May.

Both Michael (1984) and Mario Andretti (1965) are former Indy rookies of the year. Marco would be the fifth Andretti to race at Indianapolis, following his grandfather, father, uncle Jeff and cousin John. The only other families with three generations of drivers at Indy are the Foyts (A.J., Larry and A.J. IV) and Vukoviches (Bill, Bill Jr. and Bill III).

The Sebring tests on Sunday and Monday included pit stops and marked the first opportunity for the young Andretti to work with his new race crew.

“He’s definitely ready for his progression into this type of race car,” said grandpa Mario. “He looked very much at ease. He was in control and that’s what I was looking for. He’s not overwhelmed because the team was able to begin testing immediately and he gave good feedback.

“This doesn’t surprise me because I’ve seen it before in him, but you can’t confirm it until you actually see it.”

IRL technical manager Kevin Blanch watched Marco drive and was similarly impressed.

“He picked up on the changes that the crew made to the car, went back out and got right back up to speed, which shows that he knows how to evaluate the car very, very well,” Blanch said. “With some more laps under his belt, he should be a real contender by the time we open the season in Homestead.”

AP-ES-01-17-06 1320EST