'The Voice' adds Kelsea Ballerini as fifth coach for 'Comeback Stage' online series
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Grammy-nominated country singer Kelsea Ballerini has joined NBC's "The Voice" as a fifth coach for the show's new "Comeback Stage" online companion series, which premieres Sept. 24 on several platforms, including YouTube, "The Voice" official app, Instagram's IGTV, Facebook and NBC.com. The "Comeback Stage" show was revealed in August, but more details have now been announced by NBC. Season 15 of "The Voice" also premieres Sept. 24, with returning coaches Kelly Clarkson, Jennifer Hudson, Adam Levine and Blake Shelton. Ballerini tweeted, "Just call me Coach KB. So excited about this @nbcthevoice!!"

During the 10-episode "Comeback Stage" series, Ballerini will pair six contestants who were rejected in the Blind Auditions for a chance to re-enter the competition and be a part of the season's Top 13 contestants live shows that will take place in November. The six "Comeback Artists" will compete in three Battle Pairings, followed by one-on-one contests for a Battle Round. Ballerini will determine the winner of each Battle Round.

The three Battle Round winners will move on to the Comeback Stage Finals, with each performing a final song in the series. Based on these performances, Ballerini will choose the two contestants who will move on to the final phase of the series and perform live on Nov. 13 for the public's vote on the Live Playoffs Results show, in the first Twitter Instant Save of the season. The winning Comeback Artist will then decide which team he or she would like to join moving forward in the competition: Team Kelly, Team Jennifer, Team Adam or Team Blake.

"The Voice" TV broadcast will air sneak peeks of the "Comeback Stage" series on Sept. 24-25, Oct. 1-2, Oct. 8-9, Oct. 15, Oct. 22, Oct. 29 and Nov. 5.

Ballerini's second album, Unapologetically, was released in November 2017 and debuted at No. 7 on the Billboard 200 chart. In 2017, she received a Grammy nomination for Best New Artist, and she was bestowed with the Gene Weed Milestone Award at the ACM Honors.

From June 13 to Nov. 3, Ballerini is the opening act on Keith Urban's Graffiti U Tour. In 2019, Ballerini and "The Voice" season 14 winner Brynn Cartelli will be the opening acts for "Voice" coach Clarkson's Meaning of Life Tour, which kicks off Jan. 24 in Oakland, California.