* Emotional Da Silva hits first shot * Canadian starts defence of gold won 112 years ago (Adds detail on competition, quotes from players) By Steve Keating RIO DE JANEIRO, Aug 11 (Reuters) - Australia's Marcus Fraser made the most of a golden opportunity taking a three shot first round lead as golf made a subdued return to the Olympics after 112 years on Thursday with the sport's biggest names and fans staying away. Adilson da Silva, the only Brazilian in the field, was given the honour of striking the opening tee shot, receiving a smattering of applause from the sparse early morning crowd. While da Silva provided the emotional moment of the day, Britain's Justin Rose delivered the fireworks, carding the first ever hole-in-one in Olympic competition when he aced the par-three 191-yard fourth hole. More...