A valuable stud deal completed a couple of hours before Rubick raced in the Blue Diamond Prelude will have no effect on trainer Gerald Ryan's plans for the colt.

Coolmore announced it had bought a share in Rubick before he raced at Caulfield on Saturday and the two-year-old duly delivered with victory over the colts and geldings.

Despite the win, fillies Prelude winner Earthquake has been reinstated as favourite for the $1 million dollar race on February 22 and that sits pretty well with Ryan.

The two ran identical times in races with very different tempos. Earthquake powered home off a slow pace while the first half of Rubick's race was much quicker and his win was by a shorter margin and flattered those chasing him.

"I said last week if they couldn't beat him in the Prelude, the colts wouldn't beat him in the Blue Diamond," Gerald said.

"There's not a lot between him and Earthquake and we saw that.

"He ate up well last night and recovered from the race in good order."

Ryan said the $3.5 million Golden Slipper in Sydney on April 5 was not a certainty and never had been.

"This is just his first racing preparation and the Blue Diamond is the race he has been aimed at," he said.

"It's up to the horse. He will tell us whether to push on but I would be just as happy to bypass the Slipper and bring him back in the spring as a three-year-old.

"There has been no pressure from Coolmore. They love to race their horses so I don't think there's a rush to get him to stud."

One of Ryan's only concerns leading into the Prelude was that Rubick drew barrier two and would be standing in the gates for a long time.

That proved to be the case with the race delayed when one of the youngster was backed out of the barriers.

"I think he was probably in there for about five minutes but he handled it," Ryan said.

"It's all a learning experience for him and he will be better on Blue Diamond day."

Earthquake is the TAB's $2.40 favourite with Rubick at $3.10 with Nayeli, who raced a week earlier, at $8.