It is the time of the year where the two-year-olds need to start showing their credentials if they want to be players in the big autumn races.

At Caulfield on Saturday are the two divisions of the Blue Diamond Prelude (1100m), one for the fillies and another for the colts and geldings.

There have been four two–year–olds in the last 10 years to win a division of the Prelude and then claim the Group 1 Blue Diamond Stakes (1200m) at Caulfield two weeks later – Earthquake (2014), Catchy (2017), Written By (2018) and Lyre (2019).

Tony and Calvin McEvoy have set Altermatum for the Group 1 race on February 24 and the filly kicks off her latest campaign on in a Prelude on Saturday.

Altermatum started her racing career in Victoria’s first two-year-old race of the season, finishing third in the Maribyrnong Trial Stakes (1000m) in October.

The daughter of Zoustar was immediately spelled but has been given plenty of work ahead of her return on Saturday.

Altermatum was seen at the jump-outs on the Heath track at Caulfield on January 16, finishing second, and two weeks later at Geelong, again finishing second, in a 1000m trial.

Calvin McEvoy said the filly had progressed and he liked the way that Altermatum went about her work in the trial.

“We trialled her in blinkers, but we’ve got no intention of running her in them first-up,” McEvoy said.

“But it was good to see her in them as now you have them up your sleeve.

“She was good. She jumped well and then got back and she will be a filly that will be at her best over further, no doubt about that.

“She’s a classy filly. I think she can give it a shake and then the 1200 (metres) will be better for her and in time 1400 and a mile is going to be even better.”