FILE - Bobby Unser is a happy man as he accepts congratulations in the winner's circle for his triumph in the California 500 at Ontario Motor Speedway in Ontario, Calif., March 11, 1974. He beat his brother, Al, by a half second to win $70,250. Al Unser, one of only four drivers to win the Indianapolis 500 a record four times, died Thursday, Dec. 9, 2021, following years of health issues. He was 82. (AP Photo, File)

FILE - Indy 500 champs (from left) A.J. Foyt, Rick Mears, Danny Sullivan and Al Unser joke with the crowd as they stand along the pit wall at the Indianapolis Motor Speedway on Saturday, May 21, 1988. Foyt and Unser have each won the 500 four times, Mears have won twice, and Sullvian one. Mears, Sullvian and Unser will start the start from the race from the front row; Foyt has not yet qualified. (AP Photo, File)

FILE - Al Unser Jr., left, talks to his father, Al Unser, before practice at the Miami-Dade Homestead Motorsports Complex in Homestead, Fla., Thursday, Feb. 28, 2002. Unser, one of only four drivers to win the Indianapolis 500 a record four times, died Thursday, Dec. 9, 2021, following years of health issues. He was 82. (AP Photo/Luis M. Alvarez, File)