Roger James won the Tancred Stakes five years ago with star mare Silent Achiever and he is back for another shot at the Group One race with a horse he regards as the best he has trained since.

Rondinella, originally first emergency, will take her place in Saturday's $1.5 million race following the scratching of Auvray.

The lightly raced four-year-old has won four of her 11 starts and comes to Rosehill off the back of a Group One placing behind Melody Belle and Danzdanzdance in the New Zealand Stakes earlier this month.

James, who formed a training partnership with Robert Wellwood at the start of the season, regards Rondinella highly but admits he is concerned by the prospect of a heavy track.

"I've always rated her right up there. In fact, I said when she won her maiden I thought she was the best I'd had since Silent Achiever," James said.

"She was due to come across and run last week in the Ranvet, which Silent Achiever also won, but I pulled her off the plane because of the forecast.

"My biggest concern, and it's certainly a big concern, is the weather and track conditions."

Rondinella's New Zealand Stakes placing was on heavy ground, an effort that came as somewhat of a surprise to the stable considering the mare's aversion to the track conditions.

A backmarker, Rondinella didn't have the easiest passage in the race but picked herself up to make good ground behind two quality horses.

"Significantly, she was behind a couple of mares that are proven Group One performers on wet tracks and probably the two best mares racing in New Zealand at present," James said.

"She suffered considerable interference in the race and they'd gone by the time she got into gear, so her run was full of merit that day."

The Rosehill track has improved from heavy to be rated a soft 7 on Thursday but showers are forecast on race morning.

James and Wellwood will both be in Sydney for the Tancred Stakes, a race that holds mixed memories for the senior trainer.

Silent Achiever was narrowly beaten at her first attempt at the race, then known as the BMW, before avenging her defeat 12 months later.

Rondinella faces a tough ask on Saturday against the likes of Godolphin's Ranvet Stakes winner Avilius but James is confident she has the talent to feature.

"Every year is different and every horse is different but certainly you'd love to do it again," he said.