He is a five-time Australian national champion, a medalist at World Championships, a dual Olympian and an Olympic silver and bronze medallist.

[7] In 2022 he won another national open men's quad scull title in a composite Australian selection crew.

[8] In the quadruple scull at the 2016 Rio Olympics in a crew with James McRae, Karsten Forsterling and Alexander Belonogoff he won the silver medal.

[8] In 2019 he was selected with Alex Purnell, David Watts and Caleb Antill to row Australia's quad scull for the 2019 international season.

[8] With Hamish Playfair and Campbell and David Watts, Girdlestone was selected to race Australia's quad scull at the 2019 World Rowing Championships in Linz, Austria.

With Girdlestone sculling at three Australian quad kept their composure and technique and managed a bronze medal finish on the line.