Blake Shelton and Gwen Stefani recently scored a big hit with their duet "Nobody But You," their third collaboration since they began dating in 2015. However, according to Shelton's longtime producer, Stefani was a last-minute addition to the song.

Hit producer and A&R executive Scott Hendricks has been working with Shelton since the late 2000s, and is responsible for a number of the country star's big hits, from "All About Tonight" to "God's Country." He says turning "Nobody But You" into a duet was a late suggestion; in fact, the song had already been tracked, and Shelton had already laid down his vocals.

"I don't remember if it was him saying to her, 'You should sing on this,' or her saying, 'I want to sing on this,'" Hendricks shares during a phone call from his Nashville home. Stefani recorded her vocals in Hollywood, a couple weeks after Shelton did his in Oklahoma.

"It wasn't originally set to be a duet at all," Hendricks stresses. But, he adds, "she fit like a glove, and it was super easy."

Shane McAnally, Ross Copperman, Josh Osborne and Tommy Lee James co-wrote "Nobody But You." The story goes that, when McAnally tried to pitch the song to Shelton, the singer told him to send it to Stefani, who then got it to Shelton, but the artist also says he received the song in an email from Hendricks.

Hendricks remembers things a bit differently: According to him, he played both "Nobody But You" and "Hell Right," which Shelton recorded with Trace Adkins in 2019, for Shelton while they were in the car together.

"She did get a copy of the song to Blake, but I did as well, and that's okay," Hendricks says. "I'm not trying to gain credit here; it doesn't matter."

"Nobody But You" hit No. 1 in late April.

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