When the Black Crowes bring their reliable brand of anachronistic rock to town this weekend, the true draw of the evening will be supporting act Drive-By Truckers. Although often compared to Lynyrd Skynyrd by lazy scribes who can't see past the triple-guitar threat of Patterson Hood, Mike Cooley and Jason Isbell, the Truckers possess a subtle complexity that their Southern-rock forebears never had. And their new record, A Blessing and a Curse, holds its own against 2003's raggedly beautiful Decoration Day and 2004's fiercely defiant Dirty South. As powerful and graceful as those records are, though, they give little indication of just how great this band is live. Their set is so compelling, in fact, that as sure as Crowes frontman Chris Robinson will be shoeless and sporting gaudy bell-bottoms this Saturday night, you can bet the Truckers themselves will be headlining the Rocks before too long.