Country trio Rascal Flatts have had great success over the years, with many No. 1 hits, millions of records sold and membership at the Grand Ole Opry. But in this exclusive video clip, the singers admit that they haven't always been sure of their success; in fact, for a while, they were fearful of becoming one-hit wonders.

Gary LeVox, Jay DeMarcus and Joe Don Rooney sat down with Dan Rather for The Big Interview and reminisced about their debut single, "Prayin' for Daylight," which came out in 2000.

""Prayin' for Daylight" was ... actually on hold for somebody else," LeVox reveals. "And our producers at that time said, 'Hey, you know what ... let's just take this song and work with it, see what we can do.'"

The song, which was recorded as a demo and helped land the trio their first record deal, flew to the top of the charts, landing at No. 3 on Billboard's Hot Country Songs chart.

"That was 23 million records ago," LeVox says.

However, after the huge success of "Prayin' for Daylight," DeMarcus admits that the group felt a huge amount of pressure.

"... It was more a fear thing because we knew we had to follow ["Prayin' for Daylight"] up," he explains. "The first one was very, very lucky out of the box -- to have a song that did that well and broke through for us."

The Flatts' next single, "This Everyday Love," was another another uptempo song that "sort of chugged along, and it did okay," DeMarcus recalls; that song went to No. 9. The following single, "While You Loved Me," was "really slow," DeMarcus says, and peaked at No. 7. Although they'd earned three Top 10 hits with their first three singles, the country group really began to worry.

"We were at the point to where we were really starting to go, 'We really need a hit here because "Praying for Daylight" was smoking, and the last two have sort of stumbled along and stuttered a little bit," says DeMarcus.

As fate would have it, "I'm Moving On" was that hit. It won Song of the Year at the ACM Awards and, as DeMarcus says, "changed the universe for us forever."

Press play on the video above to see a snippet of Rascal Flatts' interview with Rather, which is set to air on July 28 at 8PM ET on AXS-TV. Other country stars, including Florida Georgia Line and Darius Rucker, have also sat down with the iconic anchor for The Big Interview; FGL dissected bro-country, and Rucker discussed his transition from rock to country.

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