Indianapolis 500 officials vowed on Friday to safely stage the postponed motorsport classic with 50% spectator capacity at the 250 000-seat Indianapolis Motor Speedway.
But there were no exact details on how they planned to handle more than 100 000 people with coronavirus safety protocols.
The 104th Indy 500 was originally set for 24 May at the famed 2 1/2-mile (4km) oval but the Covid-19 pandemic forced a postponement and shut down the IndyCar season until earlier this month in Texas.
"We're committed to running the Indy 500 on Sunday, 23 August and will welcome fans to the world's greatest racing venue," Speedway president J. Douglas Boles said.
"We will be limiting attendance to approximately 50% of venue capacity and we are also finalizing a number of additional carefully considered health and safety measures."
Boles did not get into specifics about how the speedway would follow such rules as social distancing and masks with more than 100 000 fans.
Typically, Indy 500 capacity can rise to near 400 000 with spectators able to drive in and park on parts of the infield area, which also include garages, seating areas, a museum and part of a golf course.
"We'll unveil the specific details of our comprehensive plan in the coming weeks," Boles said, saying the speedway would remain in touch with public health officials.
An announcement from the speedway said individuals in high-risk groups are "encouraged to consider staying home and returning in 2021."