Gwen Stefani turned to Instagram to share a throwback photo of her longtime boyfriend, Blake Shelton, on Friday (Sept. 20), proclaiming that she wishes they had met earlier in life.

The pop superstar and former No Doubt frontwoman posted a black-and-white photo of Shelton in his younger years, wearing a flannel shirt over a white T-shirt and sporting a mullet that makes him look vaguely like a young Patrick Swayze. It's not clear what year the photo was taken, but Shelton is standing in front of the offices of American Songwriter magazine in the shot.

She accompanied the picture with the caption, "@blakeshelton wish I would’ve met u sooner."

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Stefani and Shelton met while filming The Voice, and they started dating in 2015 after his divorce from Miranda Lambert and her split from Gavin Rossdale. Shelton told People in June that he can't believe they've already been together for nearly four years.

“It’s actually shocking that it has already been that long,” he reflects. "It’s kind of a blur. It still feels like it’s pretty new to me. I guess it is, relatively. Four years isn’t forever, but man, it seems like it just happened in no time.”

The couple have recently reunited in their professional lives, as Stefani is returning to The Voice for Season 17 beginning on Sept. 23. She is stepping into the coaching role Adam Levine left vacant when he decided to leave the show after 16 seasons.

Shelton has won more seasons of The Voice than any other coach in the history of the show, and he tells People he's not going to hold back as he faces off with his lady love.

"I’m not going to let her win," he says. "I’m going to have to win, but I’m going to have to do it in a way that she doesn’t feel like I beat her."

Stefani has also vowed not to go easy on Shelton. In a trailer for Season 17, when fellow coach John Legend asks if she'll be competitive with Shelton, the singer flatly states, "This is war."

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