A 23-year-old farm worker suffered head and chest injuries when his quad bike crashed into a ditch in Marlborough last night.
It is the fourth quad bike crash this week.
The share milker was flown to Nelson Hospital in the Nelson Marlborough Rescue Helicopter following the crash at a Rai Valley farm about 6pm.
He suffered moderate head and chest injuries, a spokesperson for the helicopter said.
On Tuesday, Nathan Cleverley, 40, was found with serious abdominal and pelvic injuries after his quad bike fell on top of him near the edge of a river at a Matamata farm.