FILE - In this May 30, 1967, file photo, Mario Andretti (1) leads the field at the start of the 51st running of the Indianapolis 500 at Indianapolis Motor Speedway in Indianapolis. The race had to be stopped for rain, and was restarted the following day. Gordon Johncock (3), far left, and A.J. Foyt (14), center, the eventual race winner, also compete. When it came to deciding the greatest rivalry, Foyt, Andretti and Bobby Unser received the most attention. 1986 winner Bobby Rahal says "the greatest rivalry had to be A.J. Foyt against anyone else." (AP Photo, File)

FILE - In this May 24, 1992, file photo, Al Unser Jr., top, wins the Indianapolis 500 auto race by less than a car length ahead of Scott Goodyear in the 76th running of the race at Indianapolis Motor Speedway in Indianapolis. The Associated Press has updated its survey of living Indianapolis 500 winners and their pick as the greatest race in the long history of the event. There are six races that received multiple votes, topped by Unser victory over Goodyear in 1992 — the closest Indy 500 in history. The others are Emerson Fittipaldi's win in 1989; Sam Hornish Junior's win in 2006; the 1982 battle between Rick Mears and Gordon Johncock; the 2011 race won by the late Dan Wheldon; and the 2014 thriller won by Ryan Hunter-Reay. (AP Photo/David Boe, File)

FILE - In this May 28, 2006, file photo, Sam Hornish Jr., left, pumps his fist as he beats Marco Andretti to the finish line to win the Indianapolis 500 auto race at Indianapolis Motor Speedway in Indianapolis. The Associated Press has updated its survey of living Indianapolis 500 winners and their pick as the greatest race in the long history of the event. There are six races that received multiple votes, topped by Al Unser Jr.’s victory over Scott Goodyear in 1992 — the closest Indy 500 in history. The others are Emerson Fittipaldi's win in 1989; Hornish's win in 2006; the 1982 battle between Rick Mears and Gordon Johncock; the 2011 race won by the late Dan Wheldon; and the 2014 thriller won by Ryan Hunter-Reay. (AP Photo/Dave Parker, File)

FILE - In this May 24, 1969, file photo, from left to right: Al Unser, Mario Andretti, and A.J. Foyt, the front row in the upcoming Indianapolis 500 auto race, pose for photos in Indianapolis. Andretti and Unser's rivalry is one of the most famous in the long history of the Indianapolis 500. (AP Photo, File)

FILE - In this May 26, 2019, file photo, Simon Pagenaud, of France, celebrates by pouring milk on himself after winning the Indianapolis 500 IndyCar auto race at Indianapolis Motor Speedway in Indianapolis. The milk given to winners in Victory Lane dates to 1936, when Louis Meyer professed to drink it to refresh himself on hot days. Photographers captured him guzzling from a glass bottle and the tradition has stuck. (AP Photo/Michael Conroy, File)

FILE - In this May 25, 2014, file photo, Ryan Hunter-Reay celebrates after crossing the finish line, taking the checkered flag in front of Helio Castroneves, of Brazil, to win the 98th running of the Indianapolis 500 IndyCar auto race at the Indianapolis Motor Speedway in Indianapolis. The Associated Press has updated its survey of living Indianapolis 500 winners and their pick as the greatest race in the long history of the event. There are six races that received multiple votes, topped by Al Unser Jr.’s victory over Scott Goodyear in 1992 — the closest Indy 500 in history. The others are Emerson Fittipaldi's win in 1989; Sam Hornish Junior's win in 2006; the 1982 battle between Rick Mears and Gordon Johncock; the 2011 race won by the late Dan Wheldon; and the 2014 thriller won by Hunter-Reay. (AP Photo/Dave Parker, File)

FILE - In this May 30, 1982, file photo, championship driver Gordon Johncock pilots his Wildcat-Cosworth across the finish line to take the checkered flag and win the Indianapolis 500-mile race in Indianapolis. The Associated Press has updated its survey of living Indianapolis 500 winners and their pick as the greatest race in the long history of the event. There are six races that received multiple votes, topped by Al Unser Jr.’s victory over Scott Goodyear in 1992 — the closest Indy 500 in history. The others are Emerson Fittipaldi's win in 1989; Sam Hornish Junior's win in 2006; the 1982 battle between Rick Mears and Johncock; the 2011 race won by the late Dan Wheldon; and the 2014 thriller won by Ryan Hunter-Reay. (AP Photo, File)

FILE - In this May 29, 2011, file photo, IndyCar driver Dan Wheldon, of England, crosses the finish line to win the Indianapolis 500 auto race at the Indianapolis Motor Speedway in Indianapolis. The Associated Press has updated its survey of living Indianapolis 500 winners and their pick as the greatest race in the long history of the event. There are six races that received multiple votes, topped by Al Unser Jr.’s victory over Scott Goodyear in 1992 — the closest Indy 500 in history. The others are Emerson Fittipaldi's win in 1989; Sam Hornish Junior's win in 2006; the 1982 battle between Rick Mears and Gordon Johncock; the 2011 race won by the late Wheldon; and the 2014 thriller won by Ryan Hunter-Reay.(AP Photo/Darron Cummings, File)

FILE - In this May 28, 1989, file photo, Emerson Fittipaldi, bottom, takes the lead with less than two laps remaining as Al Unser Jr. crashes into the wall during the 73rd running of the Indianapolis 500 auto race at Indianapolis Motor Speedway in Indianapolis, Ind. The Associated Press has updated its survey of living Indianapolis 500 winners and their pick as the greatest race in the long history of the event. There are six races that received multiple votes, topped by Al Unser Jr.’s victory over Scott Goodyear in 1992 — the closest Indy 500 in history. The others are Fittipaldi's win in 1989; Sam Hornish Junior's win in 2006; the 1982 battle between Rick Mears and Gordon Johncock; the 2011 race won by the late Dan Wheldon; and the 2014 thriller won by Ryan Hunter-Reay.(AP Photo/Ron Weaver, File)