Like his father before him, Donald was a stone mason, and devoted all his spare time training and competing at Highland Games. In 1870 he competed at the inaugural Powderhall Meeting, and around this time decided to become a full-time athlete. With his athletic reputation spreading worldwide, American and Canadian Caledonian Societies sponsored him to compete at their games in 1870, returning in 1872 and again in 1882. During his last visit he won a medal for mixed style wrestling in Plainfield, New Jersey at the Police Gazette Championship - regarded by many as the World Championships. Sadly, while on this trip, Donald received news from Scotland of his wife's death.
While in Australia Donald was the proprietor of the 'Croxton Park Hotel' on the outskirts of Melbourne. This was not a new venture for Dinnie as he was Mine Host at the 'Gordon Arms', Kincardine O'Neil, 'Kintore Arms', in Auchinblae, Aberdeenshire, the 'three Tuns Bar' and 'scotia Hotel' in Newcastle and even had a Funeral and Coach Hiring business in Stonehaven.
Homeward bound in 1898 he disembarked from the SS Aberdeen at Cape Town and toured the provinces for four months delighting the exile Scots with his athletic prowess and feats of strength. His favourite act was to hold a 56-lb weight in the palm of his hand on an outstretched arm parallel to the ground for up to 45 seconds. On returning to Scotland Donald, finding his popularity had declined, embarked on a tour of music halls and theatres in the north east of Scotland. He started in Aberdeen where his earlier feat in 1860, when he carried two large boulders, later known, as the 'Dinnie Stones' was legendary.