Christina Aguilera Once Tried to Punch Pink

While Pink and Christina Aguilera are now on good terms, their legendary feud that began in 2001 got so heated that Aguilera once tried to punch Pink.

During an appearance on Watch What Happens Live Thursday, Pink said Aguilera once tried to take a swing at her in a club. Pink, of course, wasn't impressed with the swing.

"I was like, 'What's happening right now? What's happening?'" she recalled.

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The feud started in 2001 when Aguilera and Pink recorded "Lady Marmalade" together and the two famously fought over who would get to belt out the high notes in the song. But as Buzzfeed and Pink point out, the two are friends today and have "made amends" on Twitter.

"She’s so talented. And deep down I’ve had bad days too," Pink said on WWHL. "She’s a really sweet person. We made up on The Voice. I mean, it was funny, I laughed. ... I hadn’t seen her in years and years and years. We became moms. We grew up. We hugged it out. It’s that simple. I feel so good about that."

When a fan called in and asked if she would record a new song with Aguilera, Pink played coy.

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"We may or may not have already collaborated," Pink teased. "I don't know if I'm allowed to say that, but I just did."

Pink received the MTV Video Vanguard Award at this year's VMAs and released her new album Beautiful Trauma earlier this month. As for Aguilera, she has appeared on The Voice periodically, most recently coaching last year.