The 22-year-old Australian says her participation at the Games, which begin in Glasgow on 23 July, was in jeopardy after scans showed injuries on her lumbar spine.

But after "further assessment" following the Australian Swimming Trials, O'Callaghan was told she would be fit to compete in Glasgow, as well as the Pan Pacific Championships which begin in California on 12 August.

O'Callaghan has won eight Olympic medals for Australia, including five golds, and is the reigning 200m freestyle world champion.

"Last month I was told I wouldn't be able to compete at Trials, the Commonwealth Games or Pan Pacs. I was also told to stop swimming immediately," O'Callaghan posted on Instagram.

"It was a moment that reinforced just how much representing Australia means to me and how badly I want to be part of this team."

Callaghan is set to compete in the 100m and 200m freestyle, the 50m backstroke and mixed relay in Glasgow, but says "things might look a little different" for her at the events.

"I'll give everything I have and do my absolute best every time I race," she added.