Thorpe comeback possible

The world and Olympic champion retired from the sport one week ago, but has reportedly opted not to remove himself from the register until he is certain he will not attempt a comeback.

"Ian is still on the drug-testing list; he has the form to complete, but we haven't got it yet," Australian Swimming chief executive Glen Tasker told The Sydney Morning Herald.

Thorpe declining to sign the papers that would remove him from the list means he is still subject to random drug testing by the Australian Sports Anti-Doping Authority (ASADA), but it also means he can return to the sport at any time.

Athletes who sign the form and are no longer subject to testing must wait a nine month period, during which they will again face random testing, before they can return to racing.

"If you change your mind, and your timing is out, there can be no comeback," Tasker said.