Blake Shelton Compares Blond Adam Levine to Meg Ryan

Blake Shelton stands and applauds next to the rest of the judges of The Voice, May 5, 2014.Trae Patton/NBC
Blake Shelton stands and applauds next to the rest of the judges of The Voice, May 5, 2014.

The top 8 artists on “The Voice” returned for another round of live performances Monday night.

But before they had the chance to sing, the coaches addressed the elephant in the room: Adam Levine's new, much-talked-about blond hairdo. When asked why he changed his hair color, the Maroon 5 frontman joked, "I don't have an explanation. I woke up, had the day off, and I thought I'd look like Shakira."

Adam said he likes how it looks on him, although he conceded that his mom hates it.

Blake and Usher teased Adam about his new 'do, with Blake comparing him to both Meg Ryan and Miley Cyrus.

"The Voice" also welcomed to its stage Pharrell Williams and Gwen Stefani, who will serve as the show's two new coaches next season. Pharrell performed his new single, “Come Get It Bae,” and also joined Gwen for a rendition of her solo hit “Hollaback Girl,” which he co-wrote.

'The Voice' Recap: Usher and Shakira Lose Another Artist

When asked what has been most exciting about joining “The Voice,” Gwen replied, "What am I not excited about? Two minutes ago I was giving birth and now I'm standing here." The No Doubt singer recently welcomed her third child, son Apollo Bowie Flynn, with hubby Gavin Rossdale.

Pharrell chimed in that the show provides an "amazing platform to be able to speak to the rest of the world."

Blake performed, too; he and former “Voice” contestant Gwen Sebastian delivered a rendition of his new single, "My Eyes."

Here's what viewers saw from the top 8: Team Blake's Sisaundra Lewis showed off her strong vocals with the Tina Turner classic "River Deep - Mountain High." She received words of encouragement from Gwen Sebastian, herself a former backup singer, during rehearsals. Sisaundra shed tears as Usher mentioned the support she receives from her mother, who was sitting in the audience. Shakira said Sisaundra has been consistent from week to week. Blake was glad that Sisaundra chose "River Deep - Mountain High."

Team Usher's Josh Kaufman took on "I Can't Make You Love Me," by Bonnie Raitt. Adam, his former coach, was happy to see how far he has come. Blake said it was as perfect a performance as he has seen in seven seasons of “The Voice.” Usher told Josh he showed the confidence of a real artist. Team Adam's Kat Perkins, who was saved by viewers during last week's results show, put a techno-rock spin on the Daft Punk hit "Get Lucky." Usher simply called it "incredible." Shakira praised Kat for staying true to herself. Adam said he knew Kat had to go big, and she did just that. He added, "Bottom three my a**."

Shakira's only remaining artist, Kristen Merlin, sang "I Drive Your Truck," by Lee Brice. Blake said she has gotten better and better since her blind audition. Shakira said she felt what the song is about, and declared, "You're not going anywhere."

'The Voice' Recap: The Live Rounds Continue

Delvin Choice of Team Adam sang R. Kelly's "I Believe I Can Fly." Blake quipped that Adam has acted like a Susan Powter, a motivational speaker, for his artists, pumping them up. Adam said there wasn't another song that Delvin could have selected for this performance.

Team Blake's Audra McLaughlin covered Rebecca Lynn Howard's "Forgive." Shakira said Audra made it seem so effortless. Blake said he was wrapped up in the performance, and that it was a good night for Audra.

Another Blake artist, Jake Worthington, performed Brooks & Dunn's "Hillbilly Deluxe." Adam said Jake comes off as very cool, even cooler than Blake. Blake said America discovered Jake as an artist with his latest performance.

Adam protégé Christina Grimmie closed the show by transforming "How to Love," by rapper Lil Wayne, into a stirring ballad. Blake called her a superstar. Shakira admired the way Christina can reach high notes. Adam said her version of the song was unique.

Three contestants will be eliminated on tonight's results show, airing at 8 p.m. ET on NBC.