Michael Freedman might be preparing to saddle up his first Australian Derby runner in his own right, but the Randwick trainer has plenty of experience when it comes to the time-honoured race.

Freedman will start Tulloch Stakes winner Wymark in Saturday's blue riband, 30 years after strapping 1994 winner Mahogany and 32 years after looking after Naturalism, both for his older brother and fellow trainer Lee.

"I haven't had a Derby runner," Freedman said.

"But I looked after Mahogany from when he was a yearling, so lots of fond memories with him, and Naturalism as well."

Mahogany won the Tulloch Stakes (2000m) as his final Derby lead-up, the same race Wymark triumphed in at Rosehill on Saturday to convince his connections to pay the $44,000 late entry fee to run.

While the former was a much more experienced horse at the same stage – Mahogany had captured the Caulfield Guineas and Victoria Derby in the spring and placed against the older horses in the Australian Cup – Wymark has been making a rapid progression.

Breaking his maiden at Newcastle in February, he went on a four-start winning streak which included an almost 10-length romp at the same track and his last-start Tulloch Stakes success.

Like most of his rivals, he will extend to 2400m for the first time in the ATC Australian Derby at Randwick after Freedman initially marked him as a sprinter-miler.

"I didn't think he was a genuine staying-type early doors, but he has well and truly proved me wrong," Freedman said.

"I always had a good opinion of him. I guess he is one of those colts that once gelded, he has just taken that next step.

"I am mindful that he has been up a while, he's not showing any signs of feeling the pinch just yet, but it takes a good, tough horse to do what he has done."

Saturday will be Wymark's hardest test against the likes of Victoria Derby hero Riff Rocket, Spring Champion Stakes winner Tom Kitten and classy filly Zardozi, especially after drawing the widest gate in 14.

But Freedman has taken heart from a conversation he had with big brother Lee prior to the son of Savabeel winning the Tulloch Stakes, a race which has produced four of the past seven Derby winners.

"I was actually chatting to Lee (on Saturday morning) and he said, 'I reckon your bloke is a great chance and it's the right lead-up race'," Freedman said.

"I thought, 'if he's telling me that then I might be heading the right way'."