The two highest-profile colts in the country will run in different states on Saturday.

But another showdown in Sydney between Pierro and All Too Hard looms as a potential carnival highlight in the coming weeks.

All Too Hard's co-trainer Wayne Hawkes confidently declared this week that he would love to see Black Caviar's half-brother meet Pierro again.

Whether it happens remains to be seen but the Randwick Guineas, George Ryder Stakes or Doncaster Mile are possible races for a clash.

Hawkes might be celebrating an Australian Guineas win for All Too Hard at Flemington on Saturday by the time Pierro steps out for the first time this year in the Hobartville Stakes 20 minutes later.

But Hawkes said he would be watching the Sydney race.

"I'd love to meet Pierro again," Hawkes said.

Pierro took care of All Too Hard in the Sires' Produce Stakes last year, the second leg of the Gai Waterhouse-trained colt's triple crown.

He beat him again when he resumed in the Run To The Rose in the spring before All Too Hard turned the tables and inflicted Pierro's first defeat in a memorable Caulfield Guineas.

All Too Hard then beat Pierro home in the Cox Plate as the pair filled the minor placings.

"I wasn't worried about Pierro. On Caulfield Guineas morning I said we could beat Pierro and most people thought I was joking," Hawkes said.

"They probably don't think I'm joking now though, do they?

"But I will be watching (Pierro on Saturday)."

Pierro is unbeaten in Sydney and is the odds-on favourite for the Hobartville.

Stable representative Mark Newnham says the Golden Slipper winner is "bigger and stronger" this preparation.

"I think he has taken another step. He's just a more mature horse," he said.

All Too Hard has already claimed two Group One races during the Melbourne carnival and his champion older sibling Black Caviar returned with a track record-breaking win in the Lightning Stakes.

Hawkes says their performances are good for racing.

"I have nothing to do with Black Caviar but I like her to win as much as the next person does. It's the same thing with Pierro on Saturday, I hope he wins," Hawkes said.

"You want to see the good horses win, unless you are in the race and then you are cheering for your own.

"We're all trying to get a good horse and we all know how hard it is to get a good horse. These horses don't come along very often, so you've got to make the most of it."

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