A woman has been flown to John Hunter Hospital in a serious condition after she came off her bike during the Port to Port MTB mountain bike race.
The Westpac Rescue Helicopter was called to the scene about 11am on Thursday.
A crew was winched down to the site of the crash, in bushland south of Pokolbin.
Fairfax Media understands the woman, 54, suffered a head injury and had to be intubated at the scene, before she was retrieved by a four-wheel-drive ambulance and taken to the Westpac chopper.
The incident came during the first stage of the four-day event, which involves mountain bike riders racing along trails through wine country, Lake Macquarie and Newcastle, taking them from Pokolbin to Dixon Park Beach.
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