NEW YORK - It sure didn't feel like a farewell.

The Rolling Stones -- average age 68, if you're counting -- were in rollicking form as they rocked the Barclays Center in Brooklyn for 2 1/2 hours Saturday night, their first U.S. show on a mini-tour marking a mind-boggling 50 years as a rock band.

And even though every time the Stones tour, the inevitable questions arise as to whether it's "The Last Time," to quote one of their songs, there was no sign that anything is ending.

"People say, why do you keep doing this?" mused Mick Jagger, the band's impossibly energetic frontman, before launching into "Brown Sugar." "Why do you keep touring, coming back? The answer is, you're the reason we're doing this. Thank you for buying our records and coming to our shows for the last 50 years."

Jagger was in top form -- strutting, jogging, skipping and pumping his arms like a man half his age. And while he briefly donned a flamboyant, feathered black cape for "Sympathy for the Devil" and later, some red-sequined tails, he was mostly content to prowl the stage in a tight black T-shirt and trousers.

The four grizzled rock icons -- Jagger, Keith Richards, Ronnie Wood and, of course, drummer Charlie Watts, were joined Saturday by singer Mary J. Blige, who sang a searing "Gimme Shelter" with Jagger, and the Texas blues guitarist Gary Parker Jr.

The band played a generous 23 songs, including two new ones, but mostly old favorites. The rousing encore included "Jumping Jack Flash," of course, but the final song was "Satisfaction." And even though the song speaks of not getting any, the consensus of the packed 18,000-seat arena was that it was a hugely satisfying evening indeed.

The Brooklyn show followed two rapturously received shows in London late last month. The band also will play two shows in Newark, N.J., on Dec. 13 and 15. Before that, they will join a veritable who's who of British rock royalty and U.S. superstars at the blockbuster 12-12-12 Sandy benefit concert at Madison Square Garden. Also scheduled to perform: Paul McCartney, the Who, Eric Clapton, Bruce Springsteen & The E Street Band, Alicia Keys, Kanye West, Eddie Vedder, Billy Joel, Roger Waters and Chris Martin.

Little green men in Red Square? "Men in Black" agents K and J may be about to recruit a new Russian assistant: Prime Minister Dmitry Medvedev. In footage recorded Friday after a TV interview, the former president joked that each Russian leader gets two folders with information about extraterrestrials that visited our planet -- and stayed. Unseen on camera footage, he is heard telling a Ren TV journalist he could not tell "how many of them are among us, because it may cause panic." He said more details could be found in Barry Sonnenfeld's "Men in Black" films.