Aitken led Resta by 240 points before the Vanderbilt Cup, held two days before the Grand Prize, with a 150-mile event at Ascot Park two weeks after.

As World War I was waged in Europe, the cars were all American-entered, including two Peugeots entered by the Indianapolis Motor Speedway for Aitken and Howdy Wilcox.

The IMS team attempted to flag Wilcox into the pits for Aitken to take over the car, but the AAA officials denied them the change.

By lap 9, Resta led from Ed Ruckstell's Mercer, the Stutz of Earl Cooper, and Eddie Rickenbacker's Duesenberg.

(The AAA, however, had set a precedent at Indianapolis by not awarding points to Eddie Rickenbacker in his relief drive.)