Injured jockey Jack Hill is showing positive signs following a race fall at Donald.

Hill's condition was revised on Monday by doctors at Melbourne's Alfred Hospital from critical but stable to serious but stable.

"This is positive news," a Victorian Jockeys Association statement said.

Hill fell from his horse in race four on Friday with the remaining four races abandoned.

He remains in the Alfred Hospital and is breathing on his own.

Sydney's leading apprentice Winona Costin will be released from Dubbo Hospital on Monday, a day after her fall at the Wellington Boot meeting.

Costin was heavily concussed in the fall and has bruising to her jaw, a lower leg and ankle.