Mariah Carey’s performance on last night’s American Idol finale was so good it had some wondering whether she hadn’t lip-synched the entire thing.

However, Mariah Carey, 43, whose voice has sounded strained in recent years, clearly wasn’t given enough credit.

A rep for Mariah Carey told Entertainment Tonight on Friday that the star sang every song live during her greatest hits medley, which included Hero, My All, Vision of Love, Make It Happen, We Belong Together and her new single #Beautiful.

While Mariah Carey’s fans raved about her performance, many on Twitter wondered whether the pop star hadn’t lip-synched.

“Hahaaa Mariah Carey’s Idol Finale Performance Could Be The Worst Lip Synching Of All Time,” wrote @FSBigBob, while @Joey O’Hern tweeted: “Mariah, you look great…but your lip-synching was off. Good try though!”

Mariah Carey’s rep, however, said not only did she sing live, but she also entertained the audience with additional songs in between live shots.

Mariah Carey’s performance on last night’s American Idol finale was so good it had some wondering whether she hadn’t lip-synched the entire thing

With former judge Jennifer Lopez scheduled to make a performance comeback later in the show, it was up to Mariah Carey to “really make the show her own”, as they often tell the contestants.

Mariah Carey stood tall in an astonishingly decadent fishtail dress replete with crystals, maribou feathers and was herself dripping in jewels.

Realizing perhaps that dancing isn’t her strongest point, Mariah Carey dispensed with any gimmicks and just stood still save for a few hand moments as she slammed straight into her incredible back catalogue.

She stormed through a seven-minute medley of some of her biggest hits, including Vision of Love, Make it Happen and Hero, before ending with #Beautiful.

The last of those songs debuted at #24 on the Billboard Hot 100 this week as Mariah Carey’s 45th entry on the chart to date.

It was classic Mariah Carey, and though some critics slammed her on Twitter for appearing to lip sync, her fans seemed generally happy with the treasure trove of powerful ditties.

Mariah Carey had a secret weapon in the form of Randy Jackson.

Her fellow judge stepped forward at the end of the song and bashfully accepted the applause still rattling away for Mariah Carey’s crowd pleasing melange.

Mariah Carey could be preparing to bring her minimum thread counts and feathered costumes to a city near you soon.

A source told E! that Mariah Carey is in discussions for a world tour and with her future on Idol looking uncertain, this could definitely be the way forward for the diva of divas.

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