Marco wins at Infineon.

Series rookie Marco Andretti scored his first IRL IndyCar win in Sunday's Indy Grand Prix of Sonoma at the Infineon Raceway.

Andretti, who started the 80-lap race from the outside of the front row, moved to the front of the field thanks to a well-timed fuel gamble from his Andretti-Green Racing team.

The driver of the #26 NYSE Dallara-Honda held off teammate Dario Franchitti in a final five lap sprint to the chequered flag to eclipse the disappointment of being pipped to the Indianapolis 500 and losing another potential win at Watkins Glen.

Vitor Meira completed the podium finishers with polesitter Scott Dixon fourth after leading the majority of the race only to fall foul of a faulty air jack during the final round of pitstops.

Helio Castroneves and Dan Wheldon finished fifth and sixth while Sam Hornish Jr, who went in to the race holding the championship lead, could only finish eighth after a mid race spin.

Castroneves now moves back to the head of the title race with a one-point margin over Hornish Jr with one round remaining. Wheldon and Dixon both remain in title contention but are 19 and 21 points behind respectively.