"When I looked in, what I saw was a girl lying on top of the mattress and a guy on top of her," Chief Elk said. "He was having sex with her and there were about 10 pairs of legs ... surrounding the bed. ... I just immediately knew that this guy is raping her."
It was the blond girl they'd seen in the kitchen -- the same girl Grolle had watched dance so provocatively. They would later find out she was 17 years old.
One at a time, Bryeans and Grolle crouched down to take their own looks.
"I saw a guy on top of her, thrusting his hips. ... I saw another guy, um, come up to her and he was forcing oral copulation on her," said Bryeans. "She wasn't moving at all. Her eyes weren't open."
Believing they were witnessing the gang rape of an unconscious young girl, the three soccer players decided to rescue her.
"A door couldn't stop us, boys couldn't stop us," Grolle said. "I mean, it was just fight or flight, and we were gonna get her out of there."
By the friends' account, they stormed the door, broke inside and raced to the girl, as members of the De Anza baseball team "casually walked out" of the room.
"When we first found her, she was unconscious," said Chief Elk.
Bryeans, 20 at the time of the house party, remembered "vomit streaming down her face."
They said it looked to them as if the girl's pants had been "ripped off."
"And, um, her body was very graphic. I mean it was clearly not consensual," said Chief Elk.
"Her panties were wrapped around one ankle," Bryeans said. "It was disgusting. It was very demeaning and very degrading."
Investigators later would determine that the vomit found on the teen was not her own.
But before that and other details of the case would come to light, her young rescuers struggled to get her to an emergency room.
"We already knew a sexual assault happened on her," said Grolle. "We just wanted her to be able to live through it."
Read Part II of "20/20" coverage of the De Anza baseball case Friday.