Sydney - Australia's Olympic silver medallist and world champion Christian Sprenger on Thursday retired from competitive swimming after struggling with a lingering shoulder injury.
Sprenger, who won the 100m breaststroke at the 2013 World Championships and silver for the same event at the 2012 London Olympics, said the injury he sustained two years ago "really took a bigger toll on me than I thought it would".
"After returning in 2015 ... I worked hard to get back what I had lost, but although I may have thought I wanted it, it wasn't enough," Sprenger said in a statement released by Swimming Australia.
"Towards the end of 2015, my breaststroke just didn't feel how it used to, and I became more and more frustrated."
The 30-year-old - who first represented Australia in 2006 - said it was a difficult decision to retire ahead of the 2016 Olympic Games in Rio.
"The Olympic gold is the only thing missing from my collection, but in this sport, if the mind and body are not perfectly in sync and focused beyond capacity, the performance will not come," he added.
"Ultimately for me, I am not there anymore, and although I may be good enough to make the Olympic team, I can't just be a number on a team, that is not who I am."