The 200-metre final went as scripted, with Usain Bolt proving his dominance yet again Thursday and Canada’s Andre De Grasse delivering another message to the sprint world.The Jamaican ran the 200 in 19.78 seconds to easily win his third straight Olympic title in the event, adding to gold from Beijing and London.It also brings his career gold medal tally to eight, including his 100 victory on Sunday.De Grasse, from Markham, Ont., comfortably took silver with a time of 20.02, a second Olympic medal to pair with his 100 bronze.France’s Christophe Lemaitre was awarded bronze, edging Great Britain’s Adam Gemili in a photo finish after both were given a time of 20.12 seconds.Afterwards, Bolt declared it his last individual race at the Olympics ahead of his retirement next year. He can add another medal in the 4x100 relay final on Friday. The Canadians also qualified.‘I don’t need to prove anything else. What else can I do to prove to the world I am the greatest?’ said Bolt.‘I am trying to be one of the greatest. Be among [Muhammad] Ali and Pele. I hope to be in that bracket after these Games.’