Imperatriz is building up to a likely start in the Gr.1 Sistema Railway (1200m) at Te Rapa on New Year's Day.

The four-year-old mare has been off the scene since finishing down the track in the Gr.1 Arrowfield Stud Stakes (1600m) and was subsequently found to have an issue.

"She's at the water walker at the moment. She was just a bit crook behind so whether she did that jumping out of the barriers last time, I'm just not sure," trainer Mark Walker said.

"She's had a break and she's good to go towards the Railway. She's had the chiropractor work on her and had a bit of acupuncture. In the back of my mind is that as a four-year-old, maybe she's going to be better at 1200m and 1400m."

A multiple Group One winner, Imperatriz was last season’s Champion Three-Year-Old and has won nine of her 14 starts.