The two-year-old filly is one of just five acceptors for the $150,000 event that kicks off Flemington's final meeting of the 2025/26 racing season.
The $20,000 Inglis Premier purchase is by Not A Single Doubt's Group 2 Danehill Stakes winner Doubtland, but out of a mare by a son of Galileo and Nichols said her two runs to date hinted that she has thrown more to the dam side.
"It's always a test when you step a two-year-old up to 1800, but she is out of a Cape Blanco mare, who's a Galileo-line stallion," Nichols, who trains in partnership with Hayden Black, said.
"There's a bit of stoutness on a female pedigree and I did feel looking at her physically that she looked like she'll get a trip.
"I'm not thinking she's a definite to target an Oaks or anything like that, but I feel she physically looks like a filly that's going to appreciate a bit of ground being a big-striding, big, rangy filly."
After finishing fifth over 1125m at Geelong on debut, Delahra was nosed out by Burning Heartz in a 1300m event at Sandown on July 1.