David Hayes is convinced He's Our Rokkii is a bigger and better racehorse for a spring campaign that has been launched with a Caulfield win.

He's Our Rokkii won back-to-back Group Three races in Sydney at the back-end of his autumn preparation and Hayes believes he could take the step up to Group One level as a four-year-old.

Defying a $4.60 to $7 betting drift in Saturday's Catanach's Jewellers Handicap, He's Our Rokkii defeated $2.45 favourite Prince Of Brooklyn by a long neck with leader Jungle Edge holding on for third, another 1-1/4 lengths away.

Hayes said the Toorak Handicap would be the first big spring target for He's Our Rokkii.

The Group One Longines Mile (1600m) and Emirates Stakes over 2000m during the Melbourne Cup carnival are also on the radar.

He said he would look to take the gelding through his classes before stepping him up in the Toorak.

"I'm convinced he's really come up. He's taken a step," Hayes said.

Jockey Dwyane Dunn agreed with Hayes about the off-season development made by He's Our Rokkii.

"He's matured into a nice horse now and he deserves an opportunity," Dunn said.

"I think he starts to come into his own once he gets to 1800 and 2000 metres. That leaves you a lot of options."