Hope Solo's 17-year-old nephew told police he PULLED A GUN on the soccer star to try to get her to stop attacking him ... but it didn't work ... this according to docs obtained by TMZ Sports.
The boy told cops ... 32-year-old Hope appeared to be drinking when she came over to the nephew's Seattle-area home and was upset because she missed a flight.
The boy says Hope thought the boy was talking smack about her and got agitated ... and then told the boy he would never be a pro athlete because he was "too fat and crazy."
The boy says he walked into another room -- but Hope followed and "called me a p**sy because I called my mom."
"I then told her to get her c*nt face out of my house," the boy said to police.
That's when allegedly Hope went on the attack -- grabbing the boy's hair and repeatedly punching him.
"I then went into a back room and got an old gun that does not work, pointed it at her and she kept coming at me. She didn't leave but walked around me cornering me like a shark."
The boy says Solo eventually left the house when he called the cops -- but then tried to get back in the house ... and started attacking the boy's mom (Hope's sister, pictured below) ... so he grabbed a broomstick and began hitting her in the head ... but she kept coming."
Hope's sister says the firearm was actually a BB gun.
Eventually, cops arrived to the home and Solo was arrested for domestic violence ... though she plead not guilty in court Monday and claims she was the real victim.