Carter Rubin Returns to 'The Voice' With Gwen Stefani to Perform New Single 'Horoscope'

The 16-year-old crooner won 'The Voice' season 19, making Gwen a first-time champion!

Carter Rubin returned to The Voice stage on Tuesday to celebrate his new single, "Horoscope!"

The season 19 winner -- who became Gwen Stefani's first-ever team member to win the singing competition last December -- debuted his new track for the audience during the season 21 Top 8 results show, thrilling this season's coaches, as well as Gwen, who was in the audience cheering him on.

Gwen introduced Carter's performance and chatted with host Carson Daly -- noting that it was the first time she'd been back at the show since Carson married her and Blake Shelton earlier this year.

"I am so proud of him," she said of her season 19 winner. "'Horoscope' is an incredible song and he's grown so much. He's such a good guy!"

Carter released "Horoscope" last month, and earlier this month, he joined Gwen onstage during her Las Vegas residency to perform Blake's part on their duet "Nobody But You" -- and got a rave review on his new song!

ET spoke with Carter after his big win last year, and he couldn't have been more excited to kick off his career with Gwen's help.

"She's so down to earth and so genuine," he raved of his coach. "She definitely wanted the best for me, she's worked so hard to get to this point. She just really believes in me, which means the world."

The Voice airs Mondays and Tuesdays at 8 p.m. PT/ET on NBC.

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