Ross announced his arrival on the international stage with a stunning gold in the 200m Breaststroke at the Glasgow 2014 Commonwealth Games, setting a Games record in the process. Gold Coast 2018 saw him just miss out on defending his Commonwealth title, closing England's James Wilby down in the final stages but having to settle for silver.
In 2015 he landed his first World title with gold as part of the 4x100m Medley Relay team, also taking bronze in the 100m Breaststroke. He went on to compete at the Rio 2016 Olympic Games and shone at the 2016 European Championships where he took two gold, one silver and one bronze. 2017 saw him back on the World Championship podium with a silver in the 4x100m Men's Medley Relay.
Following Gold Coast, posted the third-fastest time in the 100m Breaststroke heats at the 2018 European Championships but the two per nation rule meant he was unable to progress. He narrowly missed out on bronze by finishing fourth in his preferred 200m event. He struggled for form over the next few years and even considered retiring from swimming during the dark days of lockdown in 2020 but bounced back in style to qualify for his second Olympic Games in Tokyo.
Ross represented Team Scotland again at the 2022 Commonwealth Games in Birmingham, winning two bronze medals in Men's 200m Breaststroke and Men's 50m Breaststroke.