Whether to win on Friday or speculate on Saturday is the choice facing trainer Anthony Cummings with his talented filly Diamond Earth.

Cummings has entered Diamond Earth for the easier of the two possibilities at Moonee Valley on Friday night and the more difficult, but more prestigious, at Caulfield a day later.

"My feeling is that she should run at the Valley on Friday," Cummings said.

"But she has the chance to get a stakes result against her name at Caulfield."

Whatever race her trainer chooses, Diamond Earth will need to do a lot better than she did in her first-up run at Warwick Farm three weeks ago.

Having trialled well before that run, Diamond Earth finished last of 12 at Warwick Farm - but excuses have been offered.

"She got into some trouble soon after she jumped. Best to forget it," Cummings said.

Diamond Earth restored Cummings' confidence with another trial win since and has come to Melbourne in a bid to snare an early autumn success.

Her Friday assignment is in a heat of the 55 Second Challenge (955m) in which she would be one of the top fancies.

On Saturday she is down to take on some in-form open class sprinters in the Listed WJ Adams Stakes (1000m).

"It's definitely the harder race but she would benefit from even being stakes-placed," Cummings said.

Among her opposition at Caulfield is First Command, a winner at his past two starts, and the speedy ex-Darwin sprinter Canali.

A decision on Diamond Earth will be made on Friday morning.

Cummings' Melbourne team is also set to be strengthened by last weekend's Australia Day Cup winner Shadows In The Sun.

The gelding's return to form at Warwick Farm encouraged Cummings to set him for the $350,000 Mornington Cup (2400m) on February 13.

The added attraction at Mornington is qualification for the Caulfield Cup for the winner - but Cummings says he has little choice but to head south.

"In Sydney right now there's nowhere for him to go, there are just no races for him," he said.