Gary Clark Jr.

The bill for In Performance at the White House: Red, White, and Blues reads like the Mount Rushmore of living blues legends. Chisel in Austin's Gary Clark Jr. to the list.

The homegrown 28-year-old phenomenon found himself in rare company for the PBS special last month as part of the White House Blues All-Stars, led by Booker T. Jones and joined by Trombone Shorty and Mick Jagger. And Clark didn't just stand next to giants: He held his own, performing with ecstatic youth and veteran poise.

"I don't know how to explain," reflects Clark a week later. "There was no ego, no attitude. There was a lot of mutual respect. It was just smiles, heart, and antics. I'm still kind of tripping out over it"

Clark has had quite a few of those moments lately. In fact, he's experiencing an ascent to prominence not seen since Jimi Hendrix lit the UK on fire. Following his breakthrough at Eric Clapton's Crossroads Guitar Festival and subsequent 2011 debut EP for Warner Bros., Bright Lights, Clark's impressed Paul McCartney, jammed with the Roots on Late Night With Jimmy Fallon, and collaborated with Alicia Keys, that last one inspired by the R&B singer discovering Clark's rendition of "While My Guitar Gently Weeps" with Will Taylor & Strings Attached.

"She saw a video on YouTube of me doing the song down in Austin," he confirms.

More recently, Clark joined Clapton, Keith Richards, and James Cotton, among others, for Howlin' for Hubert, a tribute at the Apollo Theater to Muddy Waters' longtime guitarist Hubert Sumlin. For Clark, who performed "Shake It for Me" and "Cactus Blues," it was a natural and poignant way to pay final respects. He first jammed with Sumlin onstage at Antone's at age 15 – on a school night, no less.

"I've been playing for so long, when it's time to get up there and go, I just let go and do what I know how to do," Clark says. "I actually calm down when I get up there on stage. That's the most comfortable place for me to be."