Although Robbie Griffiths' three-year-old filly Yosemite is the rank outsider in the Thousand Guineas, the trainer doesn't see it that way.

Griffiths is certain Yosemite isn't out of place in the Group One, 1600 metre race at Caulfield on Saturday.

Griffiths said at her last start Yosemite showed she could mix it with the local fillies except for one, Instant Celebrity, who she finished seventh behind in the Thousand Guineas Prelude.

"I think Instant Celebrity could be outstanding but there wasn't much between the rest," Griffiths said.

"I think there was a half-length between second and sixth, then a gap of three lengths to my filly."

Griffiths said he felt Yosemite would have finished with that group of fillies but she had a horrendous run.

"She had an outside draw and it was our plan to be quiet on her from an outside barrier, but not for her to be three lengths behind the second last horse early in the race," he said.

"She had to use a lot of energy from the 800 metres to the 200 metres to get back into the race and then she was just burnt out by then."

Griffiths said from barrier one with Willie Pike on he expected her to settle much closer in the run, which would offset the margin between her and the group which finished in front of her last start.

"She's had four starts and the only time she didn't suffer bad luck was when she beat Poland at Bendigo," Griffiths said.

"At Flemington two starts ago, she didn't have a lot of galloping room."

Griffiths is eyeing off the Wakeful Stakes and the VRC Oaks as he believes she is a stayer in the making but he wants to see her prove that she can finish off well on Saturday.

Griffiths purchased her as a staying prospect as she has a stout pedigree being by Redwood, a Group One-winning son of High Chaparral.

"I've got to see her show she wants to run that distance and hopefully she'll do that on Saturday," he said.