Australia's world number one Kaylee McKeown [Source: Reuters]

Australia’s world number one Kaylee McKeown has withdrawn from the 200m individual medley at the Tokyo Olympics to focus on the backstroke events.

The 20-year-old’s shock decision comes two days before the swimming events start at the Games.

McKeown was among the favourites for medley gold but the event conflicts with the 100m backstroke, in which she set a world record last month.