Since Green Day relinquished what tiny semblance of street credibility they had with the fluke success of 1997's mushy ballad "Good Riddance (Time of Your Life)," it's instructive now, a couple of years later, to reevaluate what street cred really means. Friday night at the Axis was the time to do it. A small invite-only audience (kids who won tickets on the radio). No fireworks, no dancers, not even an opening act. Take that, arena rockers!

Haters, be disappointed. Old age has been kind to Green Day. Even as its members creep toward the wizened age of 30, the band still manages to be plenty spirited, not to mention more musically adept than ever before. Friday they even seemed like genuinely nice guys, to boot - projecting, if you will, an almost fatherly aura over the crowd.

Fresh off the release of Warning, their poppiest-and perhaps most mature-album yet and first since 1997's Nimrod, the Berkeley trio wasted no time in plugging the disc, opening with its first single, "Minority." From there, though, the band shied away from a greatest hits type performance, something eminently possible, in favor of a friendlier, all-request format. This slapdash approach was a stroke of genius-it drew the audience into the set and the interaction gave the group a reason to keep going.

And keep going they did: the show lasted two hours, a mammoth effort by Green Day standards. Singer-guitarist Billie Joe Armstrong, clad in his standard tie plus untucked shirt and Converse shoes ensemble, kept up an ongoing exchange with the crowd, often rambling but rarely preaching. The kids were clearly fans-there was a loud cheer for the switch to Billie Joe's standard Stratocaster guitar, affectionately known as Ol' Blue. It wasn't surprising, then, that requests ranged from early-era "Disappearing Boy," found on 1990's indie release 39/Smooth, to semi-joke track "Dominated Love Slave" from their second album Kerplunk! On the latter, a fan was brought up from the audience to play drums, but when she was unable to keep up, was half-seriously told, "You suck!"

More successful fan participation came in the form of the Fuckheads, a group haphazardly selected from the crowd to play all the instruments on a cover of the Ramones' "Blitzkrieg Bop." After a surprisingly well-played effort, the band gave props by joking, "That was a mistake. We're probably out of a job now."

Fortunately that wasn't true-this elder statesman version of Green Day has added musical competence to back up the snot-nosed attitude of yesteryear. Though the set included some 25 songs or half-completed songs, the band never seemed to tire, and sounded tight all the way through the six-song encore. With an excellent sound mix, the vocal hooks were audible and the guitar punchy and loud. Even songs from the newest album, calm by comparison on recording, came out action-packed and catchy.

And, of course, it helps to have mid-'90s alterna-megahits "Basket Case" and "When I Come Around" in your pocket for the encore.

The moral of the story: street cred doesn't mean much. It seems more like an unfortunate circumstance of economics-once a band breaks out to the mainstream, there's just no turning back, even if there's no fundamental change in the music. Refreshingly, it appears that Green Day has improved with the time and opportunity that resulted from their success. They even have hearts-Billie Joe dedicated a song to his wife on her birthday, even though she looked a bit embarrassed to be in the spotlight. And near the very end of the set, the band stopped a song entirely to issue this caring, if obvious, warning: "Take care of each other. Someone just got hurt. No show is more important than people's lives." It may not have been the punkest thing to say, but they've earned the right to stop minding that at all.