New coaches Pharrell Williams and Gwen Stefani also performed

Credit: Trae Patton/NBC/NBCU Photo Bank; Joseph Kerlakian/Rex / Rex USA

The Voice introduced its two newest coaches – Pharrell Williams and Gwen Stefani, who teamed up to perform “Hollaback Girl” – on Monday night as the eight remaining artists performed.

Team Adam Levine star Christina Grimmie followed last week’s genre-bending Drake cover with another original moment on Lil Wayne‘s “How to Love.”

The audience would not stop cheering. “You should be soaking this up right now,” Blake Shelton praised. “You look and sound like a superstar up there.”

She was not the only singer to shake up the crowd. Team Adam’s Delvin Choice tapped into the emotional connection he had with R. Kelly‘s “I Believe I Can Fly.”

With white clouds bubbling under his feet and dressed in a white suit, his moment was one part inspired gospel revival and another part pure, joyful soul.

The audience applause lingered, and when he finally got the chance to speak, Shelton summed it up. “That was as good as it gets on this show,” he told a tearful Choice. “I don’t know what Adam is doing with you guys. It’s like [’90s fitness pitchwoman] Susan Powter, getting you guys pumped up.”

The reference to the platinum-haired Powter continued a theme as the coaches teased Adam Levine about his new hair color, inviting comparisons to Miley Cyrus and a futuristic cyborg.

“I don’t have an explanation,” PEOPLE”s Sexiest Man Alive defended of his new coif. “I woke up. I had the day off and I thought I’d look like Shakira. My mom hates it. I kind of felt like that would happen.

Shelton, who last week Tweeted Levine’s private phone number, could not resist the moment. “That’s Adam? I thought Meg Ryan was sitting in with us tonight for a second there.”

After the jokefest, Shelton’s artist Sisaundra Lewis once again showed off her prowess. But her moment was a special one, marking the first time her church-going mother, 76, had seen her daughter perform on stage. Singing Tina Turner‘s “River Deep, Mountain High,” Lewis sizzled.

“You’re a pro and if you ever open the school of Sisaundra Lewis, I’m sure the four of us would enroll so you could show us how it was done,” Shakira praised.

Levine called her performance “elegant” and “potent.” Lewis seemed touched, wiping away tears and mouthing “I love you, Mom,” as her smiling mother was surrounded by cheering fans.

Usher‘s last artist standing, Josh Kaufman, offered a stylish performance of Bonnie Raitt‘s impassioned “I Can’t Make You Love Me.”

“That was probably as perfect a performance as I’ve seen on this show in seven seasons,” Shelton said. “It had magic all over it.”

The show’s three remaining country artists, Audra McLaughlin and Jake Worthington for Team Blake, and Kristen Merlin for Team Shakira, all stayed true to their roots this week. But Worthington joked that he was showing off his “redneck” side on Brooks & Dunn‘s “Hillbilly Deluxe.”

Shelton encouraged Worthington to show the crowd some “real serious and real outlaw” and he obliged in a fun romp that offered up big-time attitude. “You had me air-drumming. That’s a good sign,” Shakira told him.

The night’s biggest rock moment, however, belonged to Kat Perkins who took Daft Punk‘s “Get Lucky” and made it a metal-fest.

She jammed it out with some serious head-banging that had Usher saying that it made him wish he had long hair.

“Bottom three my ass,” said her proud coach, Levine, noting Perkins’s nail-biting viewer save from last week. “I’m on fire,” he enthused.

The Voice continues Tuesday (8 p.m. ET) on NBC when three more artists are sent home.