One of Australia's best sprinters Kayda Shaw could have run his last race, boom chaser Unlawful Entry overcome an interrupted run to break the Warrnambool track record and youngster Cactus Jack bounced into Warrnambool Classic contention with an impressive win.

Bravo said Thursday morning that Kayda Shae's future was up in the air.

"He pulled up sore. We've got a poultice on that right stopper bone and we'll leave that on for six or eight hours and then assess it," he said.

"He'll have scans in the next couple of days and we'll just have to wait and see. He ran up to those two good dogs (Asa Killa Queen and Aston Bolero) really well but you could see him falter.

"It was right on the point of the first turn when all that pressure goes on the right stopper and he couldn't drive through the turn. It's a matter of waiting and seeing what the results of the scan are."

Kayda Shae was having his first race back since being injured winning the Shootout in November last year coming off a narrow second behind Fernando Bale in the Topgun.

Bravo said recent Sandown Park record breaker Unlawful Entry showed what he was capable of after having to overcome plenty of traffic.

Unlawful Entry ran 24.71 seconds for the 450 metre trip after weaving through the field to break Aston Bolero's record set last week of 24.79.

"He's pretty good, he just needs that bit of luck early. They've done him no favours in the box draw for the final, drawing box three but if he can get a clear run he'll be in the finish," he said.

Up-and-coming sprinter Cactus Jack bounced into calculations for the $50,000-to-win Macey's Bistro Warrnambool Classic with a smart semi-final win.

More importantly Cactus Jack showed greatly improved box manners. 

The black chaser clocked the fastest semi win of 25.00, almost two lengths faster than Warrnambool trainer Ray Drew's kennel star Kilty Express (25.11) with Jason Thompson's Aeroplane Bob another length slower.

But, once again the box draw didn't help Bravo and Cactus Jack has drawn awkwardly in box five for next Wednesday night's final.

"He's a nice young dog and I have always thought he's got a pretty big future ahead," he said.

"He's a bit keen in the boxes and sometimes rocks back and forward a bit trying to anticipate the start. He'll settled down with racing and become more reliable," Bravo said.

Pre-series classic favourite Aeroplane Bob has been allocated box seven in the final with Drysdale sprinter Connemara Black drawing perfectly in box one.

In the cup final, Anthony Azzopardi's rocket Zambora Brockie should lead from box six with Aston Bolero likely to get the perfect trail from box seven.