Booker has lived up to the lofty expectations of her trainers with a strong debut win at Flemington.

Simon Zahra and training partner Mathew Ellerton said the Written Tycoon filly was the best two-year-old in their stable after Saturday's win in the Phar Lap Club Plate.

The pair considered Booker a Blue Diamond contender but shin soreness in the lead-up to the February feature resulted in the filly going for a spell.

Ridden by Andrew Mallyon, Booker was backed from $8 to $5.50 before scoring by a length from the $2.70 favourite Freeze Over, with I'll Have A Bit ($7) 1-1/4 lengths away third.

"We had her ready to go for the Blue Diamond and rushed her name through and then in her last jumpout she came up shin sore," Zahra said.

"She ended up in the paddock but has come back extremely well and this win comes off the back of one jumpout.

"We were a little worried about her condition today but she's such a professional."

Booker impressed the stable with a Flemington jumpout last Monday and were confident the filly would run well.

And Zahra said the stable did not hide the fact the filly had ability.

"There was a lot of first starters and everyone had wraps on them but they have to go and do it race day," Zahra said.

The stable will play a waiting game to see how the filly comes through her debut win.

Options include a stakes race in Adelaide or sending her for another spell in preparation for the Melbourne spring.

"The spring comes around very quickly and she will benefit from a bit of a spell so we'll let the dust settle," Zahra said.

"She's going to get a bit of ground and she's not just a quick, one dimensional filly.

"What I liked was she was up in front, on her own. Sometimes they get lost but she pinned her ears back and had a go."

Trainer John Sadler said it was his call on Freeze Over racing on her own down the grandstand side of the straight 1100m course.

Jockey Craig Newitt said Freeze Over was lost racing by herself and if she had had a mate to race with she would have won.