The Zabeel filly, which is a three-quarter sister to champion galloper Might And Power, shared the lead into the straight before kicking clear at the end to win her 800-metre trial on the No.2 grass by 13/4 lengths in 50.7 seconds.

She was bought at the 2008 Magic Millions for $270,000 by John Singleton, who races the filly in partnership with Andrew Johns and eight others who each won a share in a Bluetongue beer promotion this year.

The Opera House is eight weeks into her second preparation and yesterday was her first barrier trial, but Lees is unsure whether the filly will make it to the races this time in.

"She was a bit behind the eight ball in her first preparation, but this time she has just kept improving," Lees said.

"She is still quite green but considering this was her first trial she went real nice. It was a very encouraging effort and I liked what I saw.

"I will probably give her another trial in two weeks, but I won't be rushing her this preparation, and the first sign she has had enough will see her off to the paddock.

"Being by Zabeel, I would expect that she will get over ground later on."

Lees said The Opera House was a pure white filly but that she was not an albino.

"There is only a one-in-so-many-millions chance of getting a pure white filly and she is it," Lees said.

"It has something to do with the chromosomes, and she is just a very rare occurrence."

Lees said Healy Creek would resume over 1200m at Randwick next Saturday after the filly won her heat yesterday in 48.5, which was the fastest of the 13 trials by a half second.

Jockey Dale Spriggs settled Healy Creek in second place before cutting her loose over the final 200m, and she gobbled up early leader Country Tide to beat that gelding by a long neck.

"That was her second trial this time in and she did find the line very well," Lees said.

"She is a good filly."

Lees was also successful with Festus Hagen, which was formerly trained at Randwick by David Payne.

The gelding, which is likely to head to Brisbane, scored by a neck in 49.9.