In March 2016 Justin Clarke of the Australian Football League (AFL) team the Brisbane Lions was forced to retire at just 22 years of age due to a serious concussion sustained during off-season training two months earlier.
I marts 2016 blev Justin Clarke fra den AFL-holdet Brisbane Lions tvunget til at trække sig tilbage i en alder af 22 år, på grund af en voldsom hjernerystelse pådraget i off-season træning to måneder tidligere.