It's safe to say that Rihanna was not expecting to be outdone at her own show by a fan's vocal talents, but that's exactly what happened when she offered a concert goer a chance to sing in her mic - and her look of genuine shock has the whole internet in hysterics.

RihannaRihanna finds musical talent at her Cincinatti show

Adele got a couple of well-known YouTube stars up on to the stage to sing their Adele medley at her recent show, but Rihanna seems less keen on sharing the spotlight as she hastily took her microphone back after a fan blasted a flawless line of 'FourFiveSeconds' - her collaborative hit with Sir Paul McCartney and Kanye West - during her appearance at the US Bank Arena in Cincinnati. 

It was Broadway star wannabe Terah Stewart, a choir-trained super fan, who was lucky enough to air his gift to the world thanks to Rihanna, and the one who caused Rihanna's face to morph into that look of genuine shock before she skilfully recovered herself to finish the verse.

It was reminiscent of a show Beyonce did in Copenhagen, Denmark back in 2013, when she let a female admirer take the mic for a chorus of 'Halo', looking thoroughly impressed. Of course, Rihanna wasn't quite as generous with her fan's mic time.

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Still on her Anti World Tour, Rihanna hasn't yet commented publicly on what happened (not that she needs to - her face totally said it all), but Terah has opened up more than enough about his incredible experience. 'Y'all don't understand how long I have been riding for Rihanna. I will never forget this. She followed me too', he said, also airing his wishes to go on 'The Ellen Degeneres Show' and using his newfound Twitter popularity to plug his own YouTube channel.

Do we see a collaboration on the horizon?