Jarrod Austin is confident he has found the right race for Terra Mater to continue her winning ways, but there is one element of the contest that has him worried.

The Wandina four-year-old is the only odds-on favourite on Saturday's Randwick program, which has the Warwick Farm trainer on edge.

"I didn't realise she was the shortest of the whole day," Austin said.

"You never like to see them that short because that puts a bit of pressure on.

"But we've waited for this race in particular. Back against her own sex was a nice progression, coming from a (benchmark) 72 to a 78 against fillies and mares, but I certainly do think she can win again."

This weekend's Bisley Workwear Handicap (1300m) will be Terra Mater's third start for the campaign, following her last-start Midway win in a BM72 at Randwick and a first-up win in a fillies and mares BM72 at Canterbury, which have taken her career record to four wins and six placings from 10 starts.

"These were the three races we picked out for the prep and if she comes out and wins this one, it'll be like, 'whoa, we've targetted three races and won the whole lot'," Austin said.

"If she could win against on Saturday we'd have a few more questions on which way we go with her."

Terra Mater is 59.5kg topweight on Saturday, most of which will be made up by top jockey Nash Rawiller, and the outside barrier with Austin conceding the former is a bigger concern.

"The small field will definitely help and there's a couple of go-forward horses there, so I think there will still be a genuine tempo in the race," Austin said.

"The wide barrier is not too much of a concern, we'll leave that up to Nash, but I think she's shown she's got a good enough turn of foot to overcome that.

"If I had one big worry it would be the weight, but I think we've found the right race up against her own sex."