Nicole Auerbach, Josh Peter and Tess Quinlan

USA TODAY Sports

USC coach Steve Sarkisian said Tuesday that he's received several calls questioning the validity of cornerback Josh Shaw's story describing how he sustained two high ankle sprains over the weekend. The school is vetting the tale.

Shaw told USC's athletics web site that he injured himself jumping from a second-floor apartment balcony to the concrete below to rescue his seven-year-old nephew, who "cannot swim" and was in a pool "in distress without help nearby" on Saturday. Shaw said he rescued his nephew, who was traumatized by the experience.

Now, USC is investigating the authenticity of the story.

"I'm going to refrain from talking about the situation itself," Sarkisian said on Tuesday's Pac-12 coaches' teleconference. "I will say that Josh had never given us any indication not to believe his story. He's been a kid of very high character for us, a team leader, elected team captain. I had no reason not to believe him.

"Now, we did receive some calls that question the validity of his story. We're vetting. We're doing our due diligence on that as we speak."

A woman who identified herself as Shaw's older sister and the mother of the 7-year-old boy said the USC football player allegedly saved from drowning called reports that Shaw was actually injured during a burglary "speculation."

"I won't get involved in that," said the woman, who identified herself as Asia Shaw and spoke into front of Shaw's parents' home in Palmdale. "Those are all speculations."

Sara Faden, Public Information Officer for the Los Angeles Police Department, said there was a burglary that occurred at 11 p.m. Aug. 23 at the residence of a woman who identified herself as Josh Shaw's girlfriend. Faden said witnesses described the burglary suspect as "male, black, with dreadlocks", but, "The suspect is not Shaw. It happens to be a mutually matching descrption. No one pointed a finger at him as a suspect."

Asia Shaw said she was not at the family event during which Josh Shaw allegedly jumped from a balcony when he saw his nephew, Carter, fall into the pool. The boy cannot swim, Asia Shaw said.

She said the child was in the care of another brother, Justin. Though she said she was not at the event, she offered details of what allegedly took place.

"The one who was supposed to be watching him turned away for a second," she said. "And Josh, who is on the balcony, saw the incident and reacted."

Efforts to reach Justin Shaw were unsuccessful.

Justin Shaw works as a model, and the Los Angeles talent agency that represents them said by email that he is "isn't comfortable speaking to the media at this time."

Asia Shaw said police were not called because there was no respiratory impairment.

Deputy Jason Ames of the Palmdale Sheriff Station said that there was no record of a call out regarding Josh Shaw.

Jeff Williams, who coached Shaw at Palmdale High School, said he sent Shaw a text message to make sure Shaw was alright but has not heard back.

"I'm sure he's been inundated," Williams said after his team finished practice Tuesday. "I'm not surprised (Shaw hasn't responded)."

Addressing Shaw's character, Williams said Shaw frequently returns to Palmdale High and speaks to current players, joined USC teammates on a trip to Haiti sponsored by Habitat for Humanity and took over Shaw's father's landscaping business when his Shaw's father was recovering from surgery.

"Knowing him, the story is true," Williams said. "And I believe in him 100 percent."

Sarkisian said Josh Shaw has not changed his story since the questions emerged. According to Shaw, the incident occurred at a family social function at Shaw's cousin's apartment in his hometown of Palmdale.

"Josh is adamant with what occurred, and we're going to continue to vet some of the stories that have come across our desk or our phones and see what we have and go from there," Sarkisian told local media earlier Tuesday.

Sarkisian said he and other athletic officials need more time to vet the situation. Shaw, a senior, was chosen a USC team captain on Saturday night.

"It's important to know your players," Sarkisian said. "Josh Shaw has been a good leader for us. he's given me no reason to not believe what he told us occurred. But you need to know."

Josh Peter reported from Palmdale, Calif.