The Group 1 Australian Cup (2000m) on March 28 will lead to a potential start in the Group 1 Sydney Cup (3200m) at Randwick on April 11, weather dependent, in which he has 55kg.
"He's nominated for the Sydney Cup, but the problem would be the rain as he doesn't go a yard on a wet track," Fitzsimmons said.
"I think last year was a Good 4, but it's often very wet, so the immediate aims will be the Blamey and the Australian Cup."
Fitzsimmons said Onesmoothoperator was unlikely to have a long autumn campaign with the owners keen to have a shot at the Group 1 Caulfield Cup (2400m) in October.
Should Onesmoothoperator bypass the Sydney Cup, the Listed Mornington Cup (2400m) on April 18 and its 'win and you're in' status for the Caulfield Cup may be considered.
Fitzsimmons said Onesmoothoperator was 'casual' in his work and trials and only does as much as he needs.
"He's an interesting horse but they've found the key to him, riding him cold and let him finish off," Fitzsimmons said.
"Talking to Brian, they tried everything. Riding him closer just doesn't work, so one thing for sure is whatever race he's in, he's going to be ridden quietly to finish off."