Season 4 of The Voice will premiere on Monday, March 25 and NBC will debut two new judges this season- Shakira and Usher. They replaced seasons 1-3 judges Christina Aguilera and Cee-Lo Green.

In the episode, fans can expect to see all four judges perform an opening sequence together playing instruments. Adam Levine will play the drums, both Blake Shelton and Usher will play guitars, and Shakira will play the harmonica.

In the preview clip below, Shakira is so fiercely competitive that she mocks her fellow coaches. She jokes about Shelton's finger-pointing, Levine's need to always show off his tattoos and Usher's cockiness because he sits with his leg hanging over his chair.

Shelton said viewers can expect to see a significant increase in the way the judges compete with each other throughout the season. He pointed out that Usher and Cee-Lo Green have very different personalities.

"You know, Cee-Lo was always just so laid back anyway," Shelton told The Hollywood Reporter. "So we've replaced Cee-Lo with somebody that's just that much more aggressive."

"I think my style is just like more military than anything because I'm all about the preparation," Usher explained to THR. "But my style is to make them understand the seriousness of the craft and that they have the very best opportunity to be the greatest or the worst, you know, depending on how you take it."

In another preview clip, Shakira lets her fellow judges know that she means business.

"Never underestimate a 5-foot-3 Colombian girl!" Shakira said in the clip. "They complain that I play the lady card, but it's not a gimmick -- I am a lady! I'm not getting any advice from those guys!" she adds.

Levine said that because Shakira was pregnant during most of the season when the show was taped, she was ready to "bust some heads."

"You have a pregnant, hormonal Colombian," Levine told The Hollywood Reporter. "She's ready to bust some heads. She ain't messing around."

The Voice host Carson Daly said people underestimate the Colombian beauty and will be surprised to see how "good she is."

"I think your spring girl crush is Shakira -- a lot of people don't know a lot about her and how good she is," said Daly, who has been with the reality show since it first premiered. "I think America is really going to fall in love with her when the show is on the air," he told Us Weekly.

Christina Milian, The Voice's social media correspondent, praised Shakira. She said she is "really awesome at campaigning."

"She's smart and intelligent and gives great advice," Milian told Us Weekly.

The Voice's fourth season premieres Monday at 8 p.m. (EST) on NBC.

Watch the preview clip of Season 4 with contestant Judith Hill who gets all four coaches to turn around with her rendition of Aguilera's What a Girl Wants.

Tags: The Voice 4 Shakira Usher Blake Shelton Adam Levine