As North America’s leading three year-olds assemble at Churchill Downs, there’s a real chance Big Brown can sire a ground-breaking Kentucky Oaks – Kentucky Derby double on May 1 & 2.

The Vinery shuttler has Puca ($10) prominent in pre-post markets for the Oaks and his unbeaten colt Dortmund ($5.50) is second-favourite for the Derby. Native Dancer was the last stallion to sire a clean-sweep with Native Street (Oaks) and Kauai King (Derby) in 1966.

Puca (3f Big Brown – Boat’s Ghost by Silver Ghost) was a 16 length romper at Belmont Park in October and she’s coming off a Group 2 placing in the Gazelle Stakes (1800m) at Aqueduct. “The Gazelle winner was all alone on the lead with nobody to challenge,” trainer Bill Mott said. “She’s a chance with a little pace in the Oaks.”

Mott sent Puca for an 800m spin in 48.20s at Churchill Downs last week. “I thought it was a good, steady work,” he said. “There was plenty of horse the whole way. She galloped out very good.”

Dortmund will leave his west-coast base for Louisville on Tuesday after posting a final workout at Santa Anita. He fired a bullet 58.80s over 800m and will have one more breeze at Churchill Downs before Saturday week.

“It was a good experience for him,” jockey Martin Garcia said after the colt logged the fastest move at the distance between a couple of stablemates. “In between horses – no problem. He got a little bit dirty – no problem.”

Dortmund (3c Big Brown – Our Josephina by Tale of the Cat) extended his perfect record with a four-length victory in the G1 Santa Anita Derby (1800m) on Saturday. He’s unbeaten in 6 starts matching the marks of Kentucky Derby greats Seattle Slew (1977) and Smarty Jones (2004).

Dortmund is a battle-tested giant and that bodes well for his chances in a 20-horse cavalry charge in the Run for the Roses. There’s history on his side, too. Hall of Fame trainer Bob Baffert has prepped three Kentucky Derby winners and Big Brown won it in 2008.