Summer invariably brings oldies concert packages -- Motley Crue/Poison, Journey/ Foreigner and the unlikely combo of New Kids on the Block and Backstreet Boys. Pairing two teeny-bop vocal groups that peaked 10 years apart is either savvy marketing or mismatched boy-band nostalgia.

The mashup of NKOTBSB -- as they bill themselves in this acronym-loving world -- worked better in reality than it does on paper. Their concert Friday at Target Center thrilled 13,000 young women -- from teens to thirty-somethings -- with the same old right stuff: Flashy unison dancing; loud, brassy beats; heart-tugging, harmony-laden ballads; glittery street-styled fashions, and full-on production with flames, explosions and confetti.

Factor in the hormone-stirring nostalgia and the faded pop stars' genuine friendliness and accessibility, and the delirious women got more than they bargained for.

But first, there was a "Glee"-ful opening set by Matthew Morrison, a boy-band alum (anyone remember LMNT?). Looking like a long-haired Justin Timberlake with Jay Leno's chin, Morrison nicely suggested his "Glee" character Mr. Schue with both his cheesy cover songs and smooth dancing.

But he was quickly forgotten after the brilliantly choreographed NKOTBSB opening number. All nine singers emerged on one elevated platform on the main stage, singing Coldplay's "Viva La Vida" before they split up with BSB and NKOTB on separate hydraulic platforms on opposite stages (connected by a long runway) merging the comeback songs "Single" and "The One" amid a breathless barrage of explosions and flashing lights.

The rest of the night -- more than 30 songs over two hours and 25 minutes -- was cleverly staged as well. New Kids stepped into the crowd during "Tonight," and then the Boys made their entrance on the ensuing "Shape of My Heart" by strutting down the aisles, doling out hugs to fans while making their way to the satellite stage without missing a note.

It was a night of nonstop smiles as fans partied, depending on their age, like it was 1989 (New Kids era) or 1999 (Backstreet). Especially impressive was when all nine singers performed together on a handful of tunes (including Queen's "We Will Rock You") in what was clearly a boy-band bromance.

Despite all the excitement, the evening was hardly musically fulfilling. New Kids, who range in age from 38 to 42, sounded hopelessly dated, all Jackson 5 filtered through Prince-like synthesizers. (They did a little Prince shout-out, dancing to a recording of his "Kiss"). Despite his Michael Jackson-inspired falsetto excursions (which became annoying on "I'll Be Loving You"), Jordan Knight wasn't a distinctive lead singer. Joey McIntyre has surpassed him in both vocal chops and stage command. But bad-boy Donnie Wahlberg, a bona fide TV star ("Blue Bloods," "Band of Brothers"), was unquestionably NKOTB's true heartthrob.

Backstreet, ages 31 to 37 and a quartet since Kevin Richardson left in 2006, still sparkled on the harmonies (although with some technological enhancements). Some of their mushy ballads, especially "I Want It That Way," sounded classic. However, watching BSB again made one yearn to see their vastly superior rivals, 'N Sync. But a BSBNSYNC tour sounds about as likely as, say, Miley Cyrus and Justin Bieber hitting the road together 10 years from now.

For set lists: startribune.com/artcetera Twitter: @jonbream • 612-673-1719