Barely out of high school, the youngest Andretti is already very accomplished in racing. He ran in the Star Mazda series in 2005 after two years in Skip Barber national competition, before moving up to the Indy Pro Series. He won three races (St. Petersburg, Indianapolis and Sonoma) and finished 10th in points despite only starting half the races.
Motorsports journalist Gordon Kirby suggested at the Champ Car finale in Mexico City that the youngest Andretti would be replacing Dan Wheldon in his #26 Jim Beam Dallara-Honda for 2006 with Michael Andretti coming out of retirement to run a fifth car for his Andretti Green Racing team at the Indianapolis 500. Though a novel proposition to some, it was later confirmed in a December 15 press conference that he would move up to the Indy Racing League full time and would trade sponsors (New York Stock Exchange and Motorola) with Dario Franchitti as Andretti is not old enough to run an alcohol-sponsored car. His father, Michael Andretti, came out of retirement to run a fifth car for the Indianapolis 500.
In his rookie start on March 26, 2006 at Homestead-Miami Speedway in the #26 New York Stock Exchange Dallara-Honda, Andretti started in 13th place but made two mistakes. At the start of the race he passed too early. He then launched hard from the pits on his first stop causing a drivetrain failure. He finished near the back.
With his Rookie of the Year performance in May, he became the third Andretti to finish in the top five in his first "500" appearance, joining his father Michael (5th in 1984) and his grandfather Mario (3rd in 1965).
--Wikipedia
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