While her three-year-old stakes campaign was stymied by a worse-than-expected injury, Heartlings is ticking all the boxes to make a sound return to racing at four.

Trainer Kerry Parker says she has put her injury issues behind her ahead of Saturday's Fugen Handicap (1200m) at Rosehill.

Parker still holds Heartlings in the high regard which prompted him to run her in the Group One Vinery Stud Stakes, two Group Two races and a Group Three during the autumn carnival.

While she failed to make a major impression on those races, the reason for her underperformance was originally suspected to be a foot abscess which turned out to be a more serious injury.

"She had to have an operation on a pedal bone in her hind foot," Parker told AAP.

"It's taken a while to get over that and re-grow that foot."

Parker said the big-framed mare also had her fair share of issues with her knees but they appear to be solved.

Rather than set any major targets for the preparation, Parker said getting Heartlings back to the winner's circle was his first priority.

"It's a little bit harder now she's a four-year-old," Parker said.

"When you've got a three-year-old filly that's bred like she is you can aim at an Oaks."

With her two wins coming at 1400 and 1500m, Heartlings shapes as a horse who can build into her preparation.

"She's not as wound up as she was first-up last time," he said.

"She'll improve on whatever she does Saturday."

Heartlings is a $15 chance to resume a winner with Brisbane trainer Tony Gollan hoping $4.20 favourite Salmanazar can be his first Sydney winner since he established a base at Rosehill earlier in the year.