Trainer John Moloney had some added pressure as he left his Caulfield stables for Flemington where he had Dornier engaged in the VRC St Leger.

Before he made the journey across town for one of Victoria's oldest races onTuesday, Moloney's brother Gerard told him it time he stepped up and won the Listed race over 2800m.

Moloney's father Jim won the race with Epidaurus in 1970 while Gerard took the honours in 2000 with Teddy Bear.

Now Moloney is a winning St Leger trainer after Dornier ($19) ploughed though the heavy conditions and held on to defeat the $4.20 favourite Parthesia by a short head with High Mode ($13) 1-1/4 lengths away third.

Moloney said he began thinking of the St Leger following Dornier's last start third on a heavy track at Stony Creek on April 10.

"It wasn't until his last run at Stony Creek that I thought about running him in this race," Moloney said.

"We dodged the Galilee series because we thought they were a little stronger than him but I was pretty convinced he'd run the trip after his run at Stony Creek which is a tough track to test him out on.

"He loves the ground but it's about being able to stay which is what he did.

"When he jogged into it on the corner I thought 'hello, we're a big chance here'.

"If you watch his early runs this prep you could think there's not much happening but you've got to have owners that are patient and stick with you.

"Luckily they have and we've won a main race."

Dornier's win gave his jockey Jordan Childs a first stakes win at Flemington.

Childs' father Greg, a champion Australian and New Zealand jockey who won the St Leger on Sunday Gold in 1999, was on hand to welcome his son after the race.

Jordan Childs says there is still upside in Dornier who recorded his second win in 10 career starts.

"He didn't show much interest until I gave him a squeeze at the 1000 metres," he said.

"I was travelling coming into the corner and when I let his head go he quickened up well and made it a good staying test."