Craig Williams went from thinking he would ride the Caulfield Cup favourite to having to live on "salad and fish for the week" to switch to Amelie's Star after a dramatic Tuesday, which ended with the barrier draw.

The draw has Aidan O'Brien-trained Johannes Vermeer a firm favourite in betting for Saturday's $3.1 million staying test. But the day started with ruling favourite Admire Deus rupturing all the ligaments in a leg in his final gallop at Warrnambool and finished with Johannes Vermeer drawing perfectly in barrier two to go from a $7 chance in the morning to favourite.

Jockey Ben Melham's confidence would have had to grow with the draw and punters followed with the Irish stayer firming from $5.50 to a $4.60 Sportsbet favourite following the good gate.

"I came here and wasn't fussed about where I drew because I'm on a horse in good form that is ready to back-up well," Melham said. "That [gate two] just makes it a little better and everything is working perfectly."

The same could not be said for Darren Weir who was shattered by losing Admire Deus but will still have Humidor and Amelie's Star in the first lines of betting after drawing gate seven and 13.

"I have had better days," Weir said. "It was pretty gut-wrenching and me and my staff were pretty emotional.

"The staff become pretty attached to these horses. It was very upsetting for all involved.

"It is a very unusual injury; when I got to the vet he said he hadn't seen one of these in a few years."

Williams, a two-time Caulfield Cup winning jockey, was to have ridden Admire Deus and was swapped on to Amelie's Star, replacing Michael Dee, after the traumatic morning.

"The owners wanted to use Craig once he was available. Micky Dee was only booked at 8pm on Monday night, so it wasn't like he had been on the horse the whole preparation," Weir said. "We are trying to make the best of the situation."

Williams was happy to pick up the last start Bart Cummings winner Amelie's Star after the heart-breaking situation with Admire Deus.

"You feel for everyone involved with the horse," Williams said. "It is really one of the lows of racing but I was fortunate to pick up the ride on the mare.

"She is in good form but it is just a sticky gate for her. I really wanted to draw between one and five so she could have got the soft run she had last time.

"She will probably have to do a bit more work from that gate but she is right in the race."

Williams should be able to get down to the 51 kilograms by Saturday, despite the short notice."I could not have done 50 kilograms but it will be salad and fish for the week and I should get down to the weight," he said.

Weir was happy with gate seven for $6 chance Humidor.

"We should be able to be in the first half of the field from that gate and get his chance," Weir said.

Murray Baker is hoping for rain for Jon Snow and Bonneval after his Australian Derby winner and Australian drew gates six and 14.

"Any rain will help both of them. In is the past week I have probably turned around from thinking Bonneval is my best chance to thinking Jon Snow is now," Baker said.

"He just has the right draw to get a good run. It doesn't really worry me with Bonneval because she is going to get back and she will be charging to the line."

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