Two of the greatest names in Indianapolis 500 history -- A.J. Foyt and Rick Mears -- are battling it out in the virtual voting world to determine who will win the #ChampsOfThe500 bracket challenge.

Foyt and Mears are two of the only three four-time winners in Indianapolis 500 annals. They have advanced through a bracket challenge that started with sixteen legendary Indianapolis 500 winners to reach the championship round of voting that runs through noon ET May 23. Fans can vote for their #ChampsOfThe500 once an hour while each pairing is open by visiting ims.com/champsofthe500. 

Fans also are encouraged to tout their votes by using the hashtag #ChampsOfThe500 in Facebook and Twitter posts. The voting contest runs in conjunction with Legends Day Honoring Champions of the 500 presented by Firestone at Indianapolis Motor Speedway on May 28.

Foyt defeated three-time Indy 500 winner Helio Castroneves in semifinal voting by a margin of 65 percent to 35 percent. Mears topped the other four-time winner, Al Unser, 58 percent to 42 percent.

Vote for your ultimate #ChampsOfThe500 at ims.com/champsofthe500.