Sometimes, bands allow a fan to come onstage and sing a song with them, for the sake of a good time.

Dave Grohl did that at a recent Foo Fighters concert in Austin, Texas – and the fan surprised everyone, including Grohl. He invited an excited fan onstage to perform one of their most well-known songs, Monkey Wrench. Then, the unexpected happened, and the random fan now known as 'Kiss Guy' absolutely shredded on the guitar.

Kiss Guy was so good, Dave Grohl forgot the words to his own song.

Twitter praised the frontman and lead vocalist for giving an eager fan such a cool experience:

Grohl also serves as the lead guitarist and main songwriter for The Foo Fighters. Before forming this band, he was the drummer for the well-known grunge band, Nirvana. Casual.

And, of course, now infamous Kiss Guy:

Following his once-in-a-lifetime performance, he was identified as Yayo Sanchez. But, because of his classic Gene Simmons face paint, he will forever be known on the internet as Kiss Guy at the Foo Fighters Concert. Not a bad nickname!

One attendee confirmed that the guest vocalist was amazing:

Someone has to be pretty impressive to make a lead vocalist and songwriter forget the words to one of their most famous songs. On top of shredded on the guitar, Kiss Guy delivered top-notch stage presence alongside Grohl, proving that he could compete with the best of 'em.

Grohl might've loved it even more than the audience did.

The dude has some serious talent, and no one expected it. Check out this clip someone took at the concert:

New guitarist for the Foo Fighters? Everyone else might want to watch out...

H / T - Mashable