Hartnell won't attempt back-to-back wins in the Group I Turnbull Stakes at Flemington.
Hartnell blitzed the subsequent Caulfield Cup winner Jameka in last year's Turnbull Stakes but trainer James Cummings said the import would not clash with Winx in the $500,000 event on October 7.
Cummings told Sky Racing Radio that Godolphin booked a jockey to ride Hartnell in the Underwood Stakes before Chris Waller announced he would switch Winx to Melbourne for the Turnbull Stakes.
"We booked Kerrin McEvoy to ride the horse in the Underwood on Monday," Cummings said. "It was interesting to find out Winx is running in the Turnbull against Humidor.
"I think it's just a matter of plotting the path we think suits the horse and I think he'll run very well in the Underwood."
Cummings said the changes to the weight penalty conditions for the Melbourne Cup made the Caulfield Cup a genuine target for Hartnell but the October 21 event is one of a few options for the seven-year-old.
"I wouldn't say it (the Caulfield Cup) is the target but we are strongly considering it with the news that there is no penalty for the Melbourne Cup if we also wanted to go that way," Cummings said.
"There are still plenty of options on the table for Hartnell and he'll be telling us with the sort of form that he has got deeper on into the spring."
Cummings said Hartnell had pulled up well from last Saturday's Makybe Diva Stakes (1600m) in which he finished a well-held second to Humidor.
"I think the horse has pulled up strongly enough from a tough run in the Makybe (Diva Stakes)," Cummings said.