John Mayer Coos For Katy Perry’s ‘Roar’ Single, ‘It’s So Big’ [Video]

John Mayer has praised girlfriend Katy Perry’s comeback single “Roar” and says he knew it would be a “megaton bomb” hit as soon as he heard it.

The 35-year-old singer-guitarist said being in the studio to witness a “huge song” coming together before it even “left the stable” was a multi-layered experience.

“I remember hearing it, going like ‘Wow what an interesting experience’ to hear something that you identify as massive before it’s massive,” Mayer told Billboard this week. “I thought it was a really sweet, unforgettable sort of experience to hear someone’s work while they still have a very nascent relationship with it.

“Roar” is the lead single from Perry’s forthcoming album Prism.

The song early leaked to the Internet on Saturday and was picked up by radio stations later that same day. Digital outlets followed on Monday and the track has since hit No. 34 on the Pop Songs radio airplay chart.

“In a way you get swallowed up by it, it’s so big,” Mayer adds.

“Because it’s such an incredibly big song that it doesn’t need you to tell anybody. Million of people are going to be dancing on tables to that.

The 35-year-old singer-songwriter’s own collaboration with Perry, “Who You Love,” also leaked to the web shortly after “Roar”.

Opening up about the duet, Mayer said he wanted to write a melodic, confessional song about accepting who you love.

“It was a really fun opportunity for her to write like, her answer to [the song],” Mayer said, adding Perry wrote her own verse for the track. “So you get these two sides to this relationship that are brutally honest but no less universal.”

The music power couple have experienced multiple break-ups in their relationship but are thought to have reached a stable period in their union now.

Mayer’s new album Paradise Valley drops August 20. Perry’s Prism album rolls out on October 22.

[Image via Grammy.com]