Most roots-rock revival bands strain so hard to establish a blues groove that once they finally get it, it's no longer much fun. Sunday night at the Warner Theatre, Texas' Fabulous Thunderbirds proved just how effortless a muscular blues can sound. Even more so than on their records, these four barroom veterans (plus guest keyboardist Chuck Leavell) made their hard-rocking blues sound as natural as walking and as modern as this morning's paper.

Jimmie Vaughan is taking longer and more frequent guitar solos on stage these days, but he always played within the beat and his spaces were as eloquent as his notes. In much the same way, Kim Wilson employed pauses and accents that turned his full-bodied voice into a rhythm instrument. Drummer Fran Christina and bassist Preston Hubbard pulled off the difficult tricks of swinging even as they rocked. When it all came together on songs like Rockin' Sidney's "You Ain't Nothin' Fine," Willie Dixon's "Diddy Wah Diddy," or Wilson's own "I Believe I'm in Love," the accumulated momentum proved irresistible.

As if to throw the Thunderbirds' achievement into relief, the opening set by Omar & the Howlers showed just how pedestrian a Texas blues band can be.