Cricket Australia team doctor Peter Brukner has revealed that batsman Phil Hughes passed away as a result of a "freakish accident".

The 25-year-old failed to recover from serious head injuries after he was struck by a ball bowled by Sean Abbott during a Sheffield Shield match in Sydney on Tuesday.

It has been confirmed that Hughes, who collapsed face down on the field before being transferred to St Vincent's Hospital, suffered vertebral artery dissection.

"[The condition] is incredibly rare," Brukner told reporters. "There is only one previous example caused by a cricket ball.

"Phillip took the blow at the side of the neck and as a result of that blow his vertebral artery, one of the main arteries leading to the brain, was compressed by the ball. That caused the artery to split and for bleeding to go up into the brain, and he had a massive bleed into his brain.

"This was a freakish accident because it was an injury to the neck that caused haemorrhage in the brain. If you look in the literature there is only 100 cases reported."

Hughes, who played 26 Tests and 25 one-day internationals for Australia, never regained consciousness.