Friends have paid tribute to a young water skier fatally injured during a high-speed river race, describing her as a "champion on and off the water".
World champ Sarah Teelow came off her ski on the Hawkesbury River in the opening moments of the Bridge to Bridge Water Ski Classic on Sunday morning.
The 20-year-old sustained serious spinal and head injuries and was airlifted to the Royal North Shore Hospital but died about 8pm (AEDT) on Monday night with her parents at her bedside.
Tributes flowed for the young woman from Wellington, southeast of Dubbo, on Tuesday morning.
"I'm lost for words, such a kind-hearted person taken far to early, I'm glad we won a bridge to bridge together on an emotional day, now ur with one of ur mentors who helped u win ur world title," (sic) Dale Ashton wrote on Facebook.
Emily Rains spoke of holding her friend's hand in hospital and giving her a kiss goodbye.
"I feel so lost and gutted," she said.
"Our lives will not be the same with out you in it sare ... Love ya mate. You will forever be a champion on and off the water." (sic)
Samantha Brown described Ms Teelow as a "legend taken way before her time".
Ski Racing Australia said the tight-knit racing community was mourning the Women's World Formula Two champion.
"The ski racing fraternity is deeply saddened by Sarah's passing and extends its condolences to her family," Ski Racing Australia said in a statement.
Wellington Mayor Rod Buhr said Ms Teelow had obvious talent.
"She unfortunately suffered a fatal accident doing the sport she loved," Mr Buhr said.
NSW Police are investigating how Ms Teelow fell off her ski at high speed, including reports she hit wake created by another boat.
Ku-ring-gai Local Area Command Inspector David Hogg says police are looking at every possibility.
"We are making inquiries with the driver of the boat and witnesses to the incident," he told AAP.
Insp Hogg urged anyone who may have been filming the race and captured the fall to come forward.
A NSW Roads and Maritime Services spokeswoman said the RMS was also assisting police with the investigation.
Ski Racing Australia chairman Rick Love has previously said the conditions were good and the river was slight at the time.
Ms Teelow's mother, Tania, is also a champion water skier.
According to the University of Technology Sydney website, Ms Teelow, a bachelor of human movement student, was part of an elite athlete scholarship program.
Ms Teelow's former year 12 co-ordinator at St John's College in Dubbo, Diane Quade, says the community is in shock.
"It's just incredible to think that someone so young, with so much potential, had that cut short," she told AAP.
"It's beyond belief and very sad. We absolutely feel for the family."
Ms Quade said many people will remember Ms Teelow's personality, as well as her academic and sporting achievements.
"She was a beautiful girl with such a joyous smile, she brought so much joy with her."
