South Australian jockey Caitlin Forrest has died in hospital overnight from injuries suffered in a fall at Murray Bridge on Wednesday.

The 19-year-old had been leading the race when her horse broke down at the halfway stage, bringing down three other horses.

She was flown to the Royal Adelaide Hospital but died overnight.

Fellow jockey Libby Hopwood was taken to the local hospital before being transferred to the Flinders Medical Centre in Adelaide.

Another jockey, Justin Potter, received minor injuries but was treated and cleared at the scene.

Partner Scott Westover paid tribute to her on Facebook, saying he had lost the love of his life.

“Today has been the worst day of my life I lost the love of my life,” he wrote.

“I know there will be an angel up there watching me everyday and riding with me.

“I love you so much my beautiful girl and I’ll never forgot the best 3 years of my life I had with you.“

Forrest’s mount, Colla Voce, had to be put down.

Race caller Terry McAuliffe said it was one of his most difficult days at the race track and that Forrest was a rising star in South Australian racing.

“It’s the worst possible scenario when we have a race fall horse at the front of the field,” Mr McAuliffe said.

“Only 19 years of age, only been riding for a short time, but already carving her own name in the industry.”

He said her mother was a former jockey and now a trainer and was at the race track when the fall happened.

Thoroughbred Racing SA said they will conduct a review of the incident.

Wednesday’s incident followed the death of Queensland jockey Carly-Mae Pye after a fall during barrier trials at Rockhampton on Monday.