The 106th Indy 500 was held over Memorial Day weekend, and Season 21 winners of The Voice, Girl Named Tom, were on hand for the pre-race festivities. The sibling trio sang "America the Beautiful" — a tradition at the long-running race.

Caleb, Joshua and Bekah Leichty's voices danced beautifully around one another as they opted to sing the song a cappella. Their iconic harmonies were on full display on this day, reminding the nation why they were favored on the reality singing competition.

“Caleb, Joshua and Bekah captured the attention of America during their winning run on The Voice, and their performance will be one of the highlights of pre-race ceremonies,” said IMS President Doug Boles in a statement ahead of the race. “We welcome them back home again to Indiana along with the huge crowd on Race Day and live national TV audience on NBC and eagerly look forward to their rendition of this beautiful tribute to our great nation.”

Girl Named Tom won their season of The Voice as members of Team Kelly Clarkson. They made history as the first-ever non-solo act to take home the top prize. It was Clarkson's fourth win as a coach.

Voice coach Blake Shelton was also on hand for the annual race — he was named the Grand Marshal for the event and was given the honor of giving the command for the drivers to report to their cars. Shelton also collaborated on a helmet design for driver Jimmie Johnson, which he wore during the race. The country singer was Johnson's special guest.

Famous Singers from The Voice, Then + Now

Ten years (and counting) made a huge difference for many of the most popular singers and stars of The VoiceBlake Shelton looks noticeably different, but so do some of country music's most memorable performers.

Winners like Cassadee Pope and Danielle Bradbery wore baby faces when they auditioned during their respective seasons. The same can be said for Morgan Wallen, a forgotten castmember from the show who's transformed more than anyone else on this list of The Voice stars then and now.