[2][3] The youngest of four children born to Catherine and Vittore Turrin, Spencer grew up at Dungog, New South Wales and took up rowing in his high school years at Sydney's St Joseph's College, Hunters Hill.

[4] He was first selected to represent New South Wales in 2013 in the men's senior eight contesting the King's Cup at the Interstate Regatta within the Australian Rowing Championships.

[8] Turrin made his Australian representative debut in an U23 men's eight selected to contest the 2011 World Rowing U23 Championships in Amsterdam.

He was selected in a senior coxless four with two Olympians in Will Lockwood, Josh Dunkley-Smith and his Sydney Rowing Club team-mate Alexander Lloyd.

At the 2013 World Rowing Championships in Chungju, South Korea they won their heat and raced brilliantly in the final leading at each of the first three marks.

[10] In 2016 Turrin was selected with Lloyd to contest the men's coxless pair at the 2016 Summer Olympics in Rio de Janeiro.

[9] They took gold at the World Rowing Cup II in Poznan and then raced in the Australian men's senior eight at the WRC III in Lucerne to a silver medal.

Rowing Australia quoted Turrin after the race : “It means heaps to me, I’ve been trying for a long time to try and win something so this feels really good.

Australia had not won a men's coxless four world championship title since the Oarsome Foursome's 1991 win in the week of Turrin's birth.

[9] In their second outing of the 2018 international season, in an Australian selection eight and racing as the Georgina Hope Rinehart National Training Centre, in honour of Rowing Australia patron Gina Rinehart, Turrin won the 2018 Grand Challenge Cup at the Henley Royal Regatta[13] becoming the fourth Australian men's eight to ever do so.

At WRC III in Rotterdam and rowing behind Alex Hill, Turrin took gold in the Australian men's coxless pair.

With Turrin in the two seat the Australians kept their composure and rating and held off the Romanians in a tight finish, taking the gold in an Olympic best time.

[9] In 2022 Turrin, Hargreaves, Purnell and Jack O'Brien were selected as the men's four in the Australian squad for the international season and the 2022 World Rowing Championships.