Juan Martin del Potro has had an up-and-down career, but the start of his 2018 campaign has got the world talking.

The Socceroos have dropped to world No.68 in the latest FIFA world rankings.

Australia dropped nine places, after being ranked 59 in last month's rankings.

Iran is the top placed Asian confederation nation, currently ranked No.44 in the world.

Meanwhile, Belgium still holds the No.1 spot, followed by Argentina, Spain, Germany and Chile, who round out the top five.