UPDATE: 12:40pm A woman has been airlifted to Melbourne's Alfred hospital after the car she was a passenger in collided with an empty cattle truck near Allendale.
CFA rescue crews from Daylesford and Ballarat helped fire brigades from Crewsick and Kingston rescue the woman from the Toyota Yaris.
The woman, who had facial and arm injuries, was trapped by her legs and was freed using a hydraulic rescue tool, CFA regional duty officer Malcolm Bruce said.
Rescue crews were working on the car for almost an hour before the patient was removed, he said.
The woman was in a serious but stable condition, according to Ambulance Victoria spokesperson John Mullen.
A boy and a Sebastapol man in his 30's were also in the car at the time of the crash.
The man, who was believed to be driving the vehicle, suffered a facial laceration and cuts and abrasions.
Mr Mullen said the man, who was transferred to The Ballarat Base Hospital, was in a stable condition.
The young boy was also taken to Ballarat base hospital in a separate ambulance after being treated for minor chest injuries.
Creswick police Leading senior constable Geoff Davies said the collision occurred at the intersection of Creswick-Newstead Road and West Berry Road.
Mr Davies said an investigation would be conducted by Creswick police into the circumstances surrounding the crash and the driver had cooperated with police.