He relinquished his place in the 400m freestyle for world record holder Ian Thorpe, who had been disqualified from the event at the Australian trials.

Stevens was initially left out of the Australian team for the 2006 Commonwealth Games in his home country.

In March 2007, Stevens won his first World Championship medal after finishing 3rd in the 800m freestyle final with a personal best time of 7:48.67.

He finished 2nd behind Grant Hackett in the 1500m with a personal best of 14:53.18, making him the third fastest Australian 1500m swimmer in history.

Stevens failed to qualify for the finals of the 400m freestyle at the Olympics as he was comprehensively out-swum, finishing in 8th place in heat three, 7 seconds behind the winner.