Dunkley-Smith rows from the Mercantile Rowing Club in Melbourne. On seven consecutive occasions from 2010 to 2016 Dunkley-Smith was seated in the Victorian Men's VIII who contested the King's Cup at the Australian Rowing Championships. In those crews he saw two King's Cup victories and four times placed second. He stroked that crew in four King's Cup races.
At the 2012 London Olympics, Dunkley-Smith won a silver medal in the Australian men's coxless four with Drew Ginn, James Chapman, and Will Lockwood. Ginn's presence in the crew gave it a lineage to the successful Australian M4- crews of the 1990s that were known as Oarsome Foursomes.
In 2016 along with Will Lockwood, Joshua Booth, and Alexander Hill, Dunkley-Smith was selected in the Australian Men's Coxless four to compete at Rio 2016. They won their heat and semi-final and took the silver medal behind Great Britain in the final.
On the 10th of March 2018, he became the world's fastest 2k erg time holder with a time of 5:35.8, beating Rob Waddell's 19-year-old record of 5:36.6.
