Syd Middleton was one of two members of the Australian team that won the Olympic rugby gold medal in London to return to the Olympics. In 1912, Middleton returned as a member of the Australian eights crew, which was eliminated in the second round. In 1908, Middleton toured England with the Wallabies, the Australian national rugby union team, and played in the Olympics as part of the trip. He would again play test matches for Australia in 1910, when he captained his team against New Zealand. In all he won four caps for Australia. Volunteering for the Australian Imperial Force in World War I, Middleton fought at Gallipoli (Turkey) and France, and was awarded a Distinguished Service Order (DSO) and later made an Officer of the Order of the British Empire (OBE).