Imperatriz has failed to flatter in her final serious hit-out before her return to racing, but Michael Dee is maintaining the faith ahead of the Group 1 Black Caviar Lightning.

Dee blamed complacency for the eight-time Group 1 winner's lacklustre showing at Cranbourne on Monday morning, which saw her beaten home by Bella Nipotina, Passive Aggressive and I Am Unstoppable when a three-length fifth in an 800m trial won by Cinderella Days.

The daughter of I Am Invincible looked sharper in a 900m jumpout at Mornington on January 24 and Dee said she lacked the enthusiasm of that day or when he rode her to victory in the Group 2 McEwen Stakes (1000m) at The Valley last spring.

"She was a little bit underwhelming," Dee said.

"I would say her being here at her home track, she might have just been a little bit casual.

"I'd say she'd just be used to going out there and having a slow canter around, whereas if she was away from her home track she'd probably spark up a little bit more.

"That's all I can put her trial performance down to this morning; just being at her home track and being a little bit casual about things."

Imperatriz jumped well, settled midfield and started to improve entering the home straight but lacked the acceleration of some of her rivals, but Dee said everything else suggested she was on track for the 1000-metre Lightning at Flemington on February 17.

"I gave her a little shake-up and she didn't pick up like she usually does but I'm not too concerned," he said.

"Her action was great and she pulled up well, so we just have to trust that she's her normal self and it was just that home deck that she was a little bit casual about."

While underwhelmed by Imperatriz, Dee was impressed with the other Group 1-winning mare he rode into fifth position at Cranbourne on Monday morning with Magic Time looking well in her first public hit-out since winning the Sir Rupert Clarke Stakes in November.

"She was great, she was only out there to have a soft hit-out and I think if I shook the reins at her she would have really let down and finished off and would have gone close to winning that heat," Dee said of the Grahame Begg-trained four-year-old.

Magic Time is being set for a first-up tilt at the $1.5 million Group 1 Newmarket Handicap on March 9 and is likely to round out her preparations in a straight-track jump-out at Flemington a week before the famous sprint.