Brendan McCarthy-trained siblings Luficer's Reward and Oh So Rewarding will chase a rich prize in the inaugural running of The Showdown at Caulfield.

Saturday's Showdown carries a first prize of $500,000 and is restricted to two-year-olds by Victorian-based VOBIS nominated sires.

The two McCarthy gallopers are three-quarter brothers, both by Reward For Effort, out of half-sisters.

Lucifer's Reward is a son of Petite Briefs (by Brief Truce) with Oh So Rewarding from Oh So Petite (by Dash For Cash) with both dams out of the Snippets mare Petite Filou.

The pair were bred by Andy O'Shea and each will sport the colours of O'Shea's Innisfree Thoroughbreds in Saturday's 1200m contest.

"Knowing it was a race for Victorian horses we had the race in mind once they showed they had some ability," McCarthy said.

Lucifer's Reward was successful on debut at Moonee Valley last month while Oh So Rewarding has gone winless in six starts.

Saturday won't be the first time the pair has met, clashing in the VOBIS Gold Rush at Bendigo on March 30, finishing ninth and 13th respectively behind Prince Of Sussex.

Lucifer's Reward then went on to finish third behind Super Seth at Caulfield on April 13 with Oh So Rewarding sporting blinkers for the first time, finishing fourth at Mornington on April 7.

"The pair haven't had much luck in their last couple of starts at all," McCarthy said.

"They didn't draw too well in the race at Bendigo and I think the run of Lucifer's Reward in particular was quite good.

"He was then caught a little wide last time and I think he races best when he can get some cover and the right run.

"The blinkers improved Oh So Rewarding last time and I reckon he would have won if he'd had a bit of luck."

Early betting coincides with McCarthy's thoughts with Lucifer's Reward ($21) having the wood on Oh So Rewarding ($151) while Prince Of Sussex ($3) heads the betting over Terang debut winner Sartorial Splendor ($3.80).

Racing Victoria vets on Wednesday commenced pre-race inspections of the field of 16 and four emergencies with the Leon and Troy Corstens-trained Heka Express lame in the near foreleg.

Heka Express will be inspected again on Friday.