Jockey Andrew Adkins has been taken to Westmead Hospital following a sickening fall that has marred the opening race at Rosehill.
Adkins was aboard the Danny Williams-trained Hot 'N' Hazy who appeared to run out of room in the straight and crashed to the turf.
The colt, who Williams this week rated his best horse in a decade, suffered a broken shoulder and was treated by vets on course but was unable to be saved.
Adkins was attended to by paramedics and racing officials confirmed he had regained consciousness and was talking to medical staff.
Several jockeys, including Tommy Berry and Robbie Dolan, rushed on to the track post-race to be by Adkins' side.
Adkins was transported to Westmead Hospital and Racing NSW's Dr Duckworth later confirmed the jockey had fractured his tibia and fibula.
He also suffered seven rub fractures and a fractured clavicle which will require a plate. Surgery is scheduled for Sunday.
Adkins has endured a horror run of luck over the past 18 months, breaking several bones in a race fall at Randwick during the 2019 The Championships.
He suffered a broken wrist late last year in an accident at home and again broke a wrist in a barrier trial mishap in March.
Saturday's Sky Racing Active Handicap (1200m) was was won by Hugh Bowman's mount Smart Image, who remains unbeaten from two starts.
The horse was among several involved in the scrimmage which resulted in Adkins' fall.
Co-trainer Peter Snowden watched the race from home and said there was little joy in the win in light of the drama that unfolded.
"Smart Image looked the winner a long way from home," Snowden said.
"He was travelling so well, probably too well. Hughie didn't know whether to go out or in.
"I wish to God he had gone in."
Snowden said he felt for Adkins, whose awful run of injuries had been out of the jockey's control.
"All those falls Andrew has been involved in, he has not caused one of them," Snowden said.
"He's not a reckless jockey, he has just been terribly unlucky."
Smart Image gave the Snowdens their 38th two-year-old winner for the season and has put himself in the frame for a shot at next month's Group Three Up And Coming Stakes.
Stewards opened an inquiry into the circumstances surrounding the fall but it has been adjourned until Adkins is able to attend.