It happened on the B3081 near Verwood - he had to be cut free by firefighters.
Man Arrested After Collision
Police in Weymouth are appealing for witnesses and anyone with information to come forward after a road traffic collision in the town – with one man being arrested.
The collision, which involved a pedestrian and a silver Mazda, happened along Maiden Street at around 1.05am on Saturday, 3 September 2011.
The pedestrian, a 21-year-old Weymouth man, sustained a serious back injury and cuts and grazing to his arms and head. His injuries are not life threatening.
Police Constable Louise Brook, of Dorset Police's traffic unit, said:
"I am appealing for anyone who witnessed this collision, and anyone who saw a silver Mazda driving around the town centre at this time, to contact me urgently.
"The pedestrian sustained nasty injuries as a result of this incident and it's important that I find out exactly what happened."
A 21-year-old Weymouth man was arrested on suspicion of a motoring offence and has been released on bail while police enquiries continue.
Witnesses and anyone with information should call Dorset Police in confidence on 01305 22 22 22 quoting incident number 03:37. Alternatively, call the free and anonymous Crimestoppers line on 0800 555 111 where mobile phone tariffs may apply.
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