Dario Franchitti described himself as the invisible man heading into the Indianapolis 500, but the 34-year-old Scot was the focus for some 300,000 spectators when he won America's most famous car race on Sunday.

"When we came down to what was going to be the last restart, I looked back and saw (Scott) Dixon there," Franchitti told reporters following his victory.

"I thought, this should make people sit up and take notice."

New Zealand's Dixon finished in second place ahead of Brazilian Helio Castroneves.

"We (Dixon and Franchitti) kind of flew under the radar all month - all year actually."

While not invisible, Franchitti did go through most of Sunday's race unnoticed. Starting third on the grid, the Scotsman stayed in the rear view mirrors of the leaders until charging to the front following a restart after a three-hour rain delay.

Married to actress Ashley Judd and on a star-studded Andretti-Green race team that includes Danica Patrick and two members of American motor racing's first family, Michael and Marco Andretti, Franchitti is used to living in the shadows.

He was even upstaged by his own father George during Indy week thanks to his performance on the Brickyard Crossing golf course.

"Dad got a hole-in-one last Wednesday and we're pretty proud of him," he said.

"Michael (Andretti) asked had my dad used up all the family luck for the month."

Franchitti, who posted his 15th Indy car win, said to win the 500 was a moving experience.

"It all kind of made sense when I turned around and saw the trophy. I saw some of the names, then I was in awe," he said.

"To see the great names that are on there, it's a humbling experience."