BY JIM DeROGATIS Pop Music Critic

It was an appropriate choice for the first song in the first show of a sold-out five-night stand, and not just because Petty is playing Muddy Waters' adopted hometown.

The blues classic set the tone for an ambitious two-hour, 45-minute performance, laying out Petty's plan for this special extended stay at an intimate venue.

The Vic is the Heartbreakers' laboratory and woodshed. The goal: honing a set of the material they love to listen to on the tour bus, illustrating their roots in the sounds that preceded rock 'n' roll, with the possible plan of recording them live at Chess Studio.

There was a hint of grumbling from a few of the fans around me: In a 26-song set, Petty played only a handful of his greatest hits and concert standards. But after four decades on the road, he has certainly earned the right to indulge himself.

This was a rare opportunity to see one of the best arena acts in rock up close and personal, stretching out, jamming and taking chances that it could never take in the enormodomes. And the group delivered a truly unique experience.

Playing "name that tune" was a challenge to even the most ardent rock historians and dedicated Petty fanatics as the famously shaggy-haired, 49-year-old bandleader dug deep for obscure pre-rock nuggets and overlooked gems from his own catalog.

The most inspired cover choices included Alvin Robinson's "Down Home Girl" (which the Rolling Stones covered in 1965); JJ Cale's "I'd Like to Love You Baby"; the rampaging garage-rocker "I'm Crying" by the Animals; Buddy Holly's "Peggy Sue" (done in an unusual acoustic arrangement), and Chuck Berry's "Carol" (performed as a full-on rave-up that kicked off a three-song encore).

From his own trick bag, Petty pulled out "Angel Dream (No. 4)" from the "She's the One" soundtrack, the haunting "Blue Sunday" (one of the deeper tracks from "The Last DJ"), and the Traveling Wilburys' "Handle With Care." There were also several "mystery selections" (I have no idea where "Black Leather Woman" came from, but it was a killer tune) and some impressive new songs, among them a lovely ballad titled "Melinda" that the Heartbreakers stretched into a full-blown acoustic jam.

After Bob Dylan's current touring ensemble, there is no more fluid, subtle, or impressive roots-rock band on the scene today. As they've been through much of his career, Petty's secret weapons were the amazingly versatile keyboardist Benmont Tench and longstanding lead guitarist Mike Campbell, who was as impressive firing off leads on his Les Paul during the louder numbers as he was while finger-picking an electric mandolin during the 12-song acoustic set.

This is not to slight the other Heartbreakers. Newcomer Scott Thurston is a sensitive third guitarist, expert at carving out unique spaces between Petty and Campbell as well as singing spot-on backing vocals and playing spirited harmonica. And the band's original bassist, Ron Blair (who replaced the late Howie Epstein), and drummer Steve Ferrone formed a truly impressive rhythm section that was able to stop and shift gears on a dime with one wave of Petty's arm.

The boss is clearly proud of this band, and he took an obvious joy in putting it through its paces onstage at the Vic in a radically different style and setting than the show he presented at the United Center in December.

Whether or not this was the show that Petty fans expected, they left having witnessed an inspired, energetic, revealing and consistently thrilling performance--a gift from one of rock's greats.