'The Voice': John Legend calls country singer 'boring,' Gwen Stefani steals him from fiancé Blake Shelton

Usher has a confession – He's back on "The Voice."

The eight-time Grammy winner returned to the NBC singing competition Tuesday during the first round of knockouts. And he knows a thing or two about "The Voice," because he served as a coach on Seasons 4 and 6, winning the latter.

"Back at it again," Usher said. "I love being a mega mentor. I love being at 'The Voice.' It’s just my home away from home, especially during these hard times."

His return felt extra homey, thanks to Blake Shelton's familiar dad jokes: "Remember when I used to call you Gusher and Blusher and Crusher. That was funny."

"Yeah, that was really unique," Usher sarcastically quipped.

'The Voice': Gwen Stefani threatens to quit after battling teens nail John Legend song

Usher admitted he was out of his league during the country showdown between Blake Shelton's trio Worth the Wait and Ben Allen.

Here's how the Knockout Round works: Each coach pairs two singers on their team, but unlike the Battles duets, each contestant selects and sings their own song.

Unless you are a trio. Worth the Wait opted for Tanya Tucker's "Delta Dawn," which Shelton labeled "Country 101." The group, made up of a mother and her teen daughters, dedicated the song to their Papa Bud, who was recently diagnosed with COVID-19.

Allen also had a special someone in mind when selecting Luke Combs' "She Got the Best of Me": his wife Laura.

John Legend had some interesting feedback for Allen: "You’re so good and you’ve been so good every round. I think it’s kind of boring." Ouch?

What Legend meant to say, however, is that he himself is "getting boring being repetitive about how good" Allen is.

Shelton ultimately dubbed Worth the Wait the winner: "I think it’s time that a trio makes it to the finale on this show and I think Worth the Wait is the ones," Shelton said.

His fiancée, Gwen Stefani, instantly hit her steal button for Allen, earning a big bear hug from Shelton. "Oh, we can make out," she joked.

The rocker felt it was a natural choice, echoing her own transition to country music.

"Ben had one of my favorite performances," Stefani said. "I feel excited to have country on my team. I’m on country music//this is the full quote, right? no 'radio'? right now with Blake Shelton, so it just feels right."

"The Voice" Knockouts continue Monday at 8 EST/PST on NBC.

This article originally appeared on USA TODAY: 'The Voice': Gwen Stefani steals fiancé's 'boring' country singer