Lightly-raced filly Dual Chamber confirmed the Shoot Out form line was the best of the three-year-old generation when she notched her first black-type win at Doomben.Having her first start for Toowoomba trainer Rex Lipp, Dual Chamber went into Saturday's $100,000 Bright Shadow Handicap (1200m) with a win over Shoot Out at Eagle Farm three runs back.And less than an hour after Shoot Out stormed home in the AJC Australian Derby, Dual Chamber proved her victory over him was no fluke when she finish

Lightly-raced filly Dual Chamber confirmed the Shoot Out form line was the best of the three-year-old generation when she notched her first black-type win at Doomben.

Having her first start for Toowoomba trainer Rex Lipp, Dual Chamber went into Saturday's $100,000 Bright Shadow Handicap (1200m) with a win over Shoot Out at Eagle Farm three runs back.

And less than an hour after Shoot Out stormed home in the AJC Australian Derby, Dual Chamber proved her victory over him was no fluke when she finished powerfully to beat a quality field of fillies and mares in Saturday's Listed event.

Ridden by Jason Holder, Dual Chamber ($5) sprinted quickly in the straight to defeat Acquired ($6) by three-quarters of a length with Tracy's Choice ($4.40 fav) running a big race at just her third run to finish a short neck back third.

Lipp was full of praise for Dual Chamber.

"We trialled her twice and learnt a bit about how to ride her and it worked out well," Lipp said.

"I've only had her for this preparation but she impressed me right through and I think a race like the Queensland Guineas would be perfect for her."

Holder said Dual Chamber impressed him.

"Rex wanted her to relax and finish it off and she really sprinted when I let her go," Holder said.

"And the best thing is she will improve a lot with that run under her belt."

Earlier, trainer Jason McLachlan set his sights on another Group One winner after consistent filly Bella Sirena broke a stable drought in bold fashion.

Bella Sirena went into the $50,000 Race-Tech Australia Handicap (1350m) with a record of one win and seven placings from 15 starts but emerged as a filly of the future and a genuine Queensland Oaks contender, according to McLachlan.

"She mightn't have the class but she'll stay all day and she's tough," an emotional McLachlan said.

"It's such a great thrill to win a race for one of her owners Kevin Copra. He's been my most loyal client since I started training 10 years ago."

Bella Sirena ($11) gave emerging apprentice Justin Wood the second leg of a winning double when she ran home powerfully to nab Alberton Park ($3.70 fav) right on the line for a nose win with Pinpoint Accuracy ($6) a short half-head back third.

Less than length separated the first four placegetters with Hallmark Star ($4) steaming home from back in the field to grab fourth in a race in that promises to be a solid pointer to the winter carnival.

McLachlan shot to national prominence when he teamed with his late father Bruce to win last year's Golden Slipper with Phelan Ready but he has endured a lean trot in the city in the past few months.

"I've got a saying that if I get any more seconds, I'll be a minute," he said.