Police say the 62-year-old man was "clipped" at the intersection of Dunlop Street and Hart Drive, at 8 p.m. on Monday.
The driver stopped and assisted the man, who was taken to hospital.
Police alleged the man was at fault.
When they went to talk to him in hospital, they learned his injuries were more serious than initially believed.
Police say he's being treated in a Toronto hospital for vertebrae and lung-related injuries.