A woman who had voluntarily participated in a "smack fest" at a St. Paul bar this past weekend was later attacked by her opponent outside, police said.

The two women had faced off in a "smack fest" at Arnellia's early Friday, said police spokesman Steve Linders. It's unclear who won the contest, and why one woman later allegedly attacked the other, he said.

"A smack fest is described as a competition in which willing participants take turns smacking each other," Linders said. "After the competition, [the women] spoke and neither seemed upset about the outcome of the contest."

But when the victim left the University Avenue bar around 2-2:30 a.m. Friday, she found herself confronted by her opponent, the women's boyfriend and five to six other people.

According to police: The opponent punched the victim in the nose and knocked her to the ground.

The boyfriend "stomped" on the left side of the victim's face. Others also joined the attack.

The woman suffered swelling on the left side of her face, and "significant" bruising on both sides of her face, Linders said. She also suffered cuts, and was bleeding "a lot."

There have been no arrests in the case.

Chao Xiong • 612-270-4708

Twitter: @ChaoStrib