Victory in the Group Two Sandown Guineas has saved the manhood of Petrology.

And the three-year-old will now be set for the stallion-making race, the Australian Guineas at Flemington in March.

Ridden by Nick Hall, Petrology, backed from $18 to $14, scored by 2-1/4 lengths from the favourite Stratum Star ($3.20) with Berisha ($101) 1-1/4 lengths away third.

Following Petrology's victory over 1800m at Flemington on VRC Oaks Day, trainer David Hayes said the Sandown Guineas would decide if three-year-old would have an appointment with the surgeon's knife.

"He's certainly not getting gelded now," Hayes said.

"He was still a bit of a handful but my eldest son (Ben) strapped him today and did a good job with him."

Hayes, who landed his second Sandown Guineas following Cayambe's win in 2005, revealed that Petrology had been vetted for sale to go to Hong Kong during the week but the deal had fallen through.

He said the colt didn't having a high enough rating to go as a replacement permit horse and although he would have one now, he is not for sale.

With the sale falling through Hayes said he is now looking to Petrology being a Group One performer and believes the son of Fastnet Rock may eventually turn into a weight-for-age horse.

"He's pretty valuable now I reckon," Hayes said.

"That was a win of a good horse, a weight-for-age horse going forward.

"I'll put him away now. He's stepped up on the big stage twice now and he might be an Australian Guineas horse in the autumn."

Hall believes the Australian Guineas would be an ideal race for the colt.

"David said they have done a lot of work with him being a colt to get his racing manners right, so we didn't want to wreck that today," Hall said.

"So we went back and finished off really strong.

"It was a good win by a good horse."