Gavin Rossdale Joins Gwen Stefani as Guest Mentor in 'The Voice;' Talks About Serious & Competitive Adam Levine

Gavin Rossdale, Gwen Stefani's husband, will join this year's season of "The Voice" as a guest-mentor judge.

Access Hollywood broke the news and had an exclusive interview with Gavin Rossdale and Gwen Stefani about their stint in one of the biggest singing competition on television, while NBC's "The Voice" has also tweeted about the Bush vocalist's participation in the program.

Gavin will serve as a guest-mentor for Gwen's team where the latter have to slash out some proteges to come up with final contenders for her team until the finals.

"He is super articulate and he has a really good opinion and he is smart and he's been doing a really good job," Stefani said in the interview when asked how she finds Gavin as a guest-mentor.

Gavin Rossdale, on the other hand, promised to make sure that Gwen will be of the same caliber as the other judges.

"The main thing, from my perspective, is just to make sure that Gwen is so good and excellent like all the other judges on the show, he said about the news on Gavin Rossdale joining "The Voice."

"It's just sort of to not interrupt and to normally let her speak, let her do her thing and I'm just like a side thing," he added.

Gwen will replace Christina Aguilera as the sole female coach in the show, as Aguilera is reportedly pregnant with her second child.

Gwen said that Christina has wrote a note for her and recently attended her son Kingston's birthday party. "She's all girl power. ... She's like, 'You're gonna love it, you're gonna be fine," Stefani said about the former The Voice coach.

Gwen will be seating with resident coach Adam Levine and Blake Shelton as well as fellow new recruit Pharrel.

The "Hollaback" singer also said that the Maroon 5 frontman is childish and unsportsman-like in the show; Stefani rebutted and said she loved it, though.

"Adam is like an eight year old boy who has never learned sportsmanship...which I love because it reminds me of home. I think that he is like so serious about this game that we are playing. I mean he seriously gets upset. It's crazy," the Daily Mail quoted her saying.

The Voice will return on television on September 22.