A Golden Slipper campaign has been ruled out for smart juvenile Champagne Cath but leading trainer Chris Waller unveiled another youngster with autumn carnival potential at Rosehill on Saturday.

Waller was trackside as he produced an early double in the first two races before returning to the Gold Coast for the rest of the Magic Millions yearling sales.

Two-year-old Calming Influence got things rolling for Waller when she turned in a professional display on debut in the Onemorenomore First Crop Plate (1100m).

Odds-on favourite Royal Descent ($1.65) then made light work of her rivals in the Australian Turf Club (1400m), maintaining her unbeaten record with a 2-3/4 length victory.

Calming Influence, sent out the $2.60 favourite, pressed forward to take up the running and kicked strongly in the straight to defeat Dream Forward by a length with 1-3/4 lengths to Miniature in third.

Waller will now look to stakes races for Calming Influence in the autumn.

"We've got a bit of time to buy now and obviously a lead up to the Slipper is first and foremost for any horse to get some black type," Waller said.

"And the dream is beyond that.

"She's got a lot of ability and is professional as well.

"We've still got a bit of fine tuning to come. But this is a very good start."

Waller revealed after the race that Champagne Cath would miss the rest of the season through injury.

Champagne Cath was an impressive debut winner at Rosehill last month and was getting ready for the Magic Millions before she was ruled out of that race late last month.

It was hoped she might still be able to play a part in the autumn but Waller said scans this week ruled that out.

"She'll miss the Slipper," Waller said.

"She's got a stress fracture in a hind leg. It's not significant. She's allowed to start working in 12 weeks.

"It's disappointing but worse things can happen. And I always knew she wasn't a real two-year-old."

AAP TURF