Manners aside, they're girls on a roll

The opening whistle shrieks.

Within seconds, silver-clad Cosmonaughties and menacingly tutued Nutcrackers rocket themselves into a multiskater pileup.

Bones crunch, music thumps, fans scream.

Not the kind of thing normally happening at an art school, but such is the scene at the Massachusetts College of Art gymnasium on Saint Patrick's Day, when the Boston Derby Dames, a three-team, ''all-girl" roller derby league, as they call themselves, make their local debut.

Advance billing for the ''Shamrock Showdown" has promised flat-track mayhem to the capacity crowd of 600. The goal, as in roller derby of old, is for each team to get a designated skater -- the ''jammer" -- ahead of the other team's four ''blockers" while preventing that team's jammer from doing the same. All of this is done on a track, marked out on the floor in black tape, that's barely wide enough for three to skate side by side. The Dames will tell you showmanship is part of the equation. But make no mistake: This is a real sport.

''We practice four nights a week, two-hour practices. We train very hard," says Roxy Redlight, known to her Simmons College classmates as Olivia Gatti, librarian-in-training. ''It has this stigma from the '70s of being fake, but all the passion on the track is very legitimate."

That stigma comes partly from roller derby's onetime association with professional wrestling. But any suspicions the crowd might have had that the evening's action is choreographed evaporates when Jodi Faster (aka Libby Adams of Dorchester) is sent sprawling while attempting to pass someone, and, a short time later, a brief but apparently real fistfight erupts when one skater seems to feel she's been wrongly taken down.

''We have a lot of team pride," says Evilicious, whose civilian alter ego is Eva McCloskey, mild-mannered public relations professional. ''When we're on the court, we're on the court. We're going to go have a drink with these ladies after and we're going to hug and kiss and it'll be great, but not when we're bouting."

That distinction seems to be a large part of the appeal for many of the Dames, who came to roller derby from a variety of athletic and professional backgrounds but share a desire to trade their workday personas for helmets and elbow pads. They create personas such as Full Metal Jacque, Violet Rage, and Malicen Thunderland, and knock the heck out of one another one lap at a time.

Formed last spring by Ivana Clobber, formerly a member of a Providence-based league, the Dames had their first matches on the road in Providence and Las Vegas, and they plan to have a full May-to-October season this year at venues to be determined -- preferably some that could accommodate the several hundred fans who were turned away from the St. Patrick's Day Showdown.

The league is skater-owned and operated, ensuring that whatever happens next will be determined by the Dames and only the Dames, whether they're throwing each other down on the track or throwing a few drinks back afterward, as they did at the after-party at the Linwood Grill near Fenway Park.

''It is so much fun, and it's so much about sisterhood," says Emily Shepard of Belmont, an elementary school science teacher who, as ''Ginger Slap," wears the number 7800° F, the estimated temperature of the Earth's core, as a member of the Nutcrackers.

''It's a place to get your aggressions out, but it's also a really cool place to meet new people and new women," she said.

Though the Mass Art event is the sport's first night in town, nearly all of the skaters seem to have cheering sections in the crowd, and more than a few are singled out for heckling, which some of the Dames return with smiles and creative hand gestures.

After three rounds, the Nutcrackers edged out the other two teams to come in first. But more importantly, the Dames had delivered on their promise of full-contact sporting entertainment.

''It felt amazing to go out there and see people cheering and holding up signs," said Roxy Redlight, the future librarian, after the event. ''The booing and hissing and the cheering was awesome. I love that people hated us and loved us."

Wil Kilburn can be reached at ciweek@globe.com