A capacity field of 20 will contest South Australia's premier sprint race, The Goodwood at Morphettville.

Topweight, and favourite, Vega Magic will on Saturday attempt to become the first horse since Musket Belle in 1911/12 to win the race in successive years.

In victory last year Vega Magic became the first horse to win the race first-up and he will be attempting to do the same 12 months later.

He will carry 59kg, 2.5kg more than last year and has barrier 14 after jumping from gate six in 2017.

After Tuesday's barrier draw Vega Magic remained the solid $2.60 favourite for the $1 million Group One sprint in which he will be ridden by Damien Oliver.

After being a late scratching from last week's Doomben 10,000 after striking his head when being saddled, stablemate Thronum has been flown to Adelaide to take his place.

He has drawn barrier seven and has firmed from $26 into $13.

Champion trainer Darren Weir will saddle three runners as he attempts to replicate Black Heart Bart's win in 2016.

He has Voodoo Lad (barrier 1), Stellar Collision (17) and Handsome Thief (12) engaged.

Melbourne mares Missrock and Secret Agenda, second and fourth respectively behind Vega Magic last year, are back again with Secret Agenda a $10 chance and Missrock quoted at $26.