Casey Lock was questioning her father’s (trainer Peter Lock) sanity when he outlaid $2,000 for a two-year-old filly at New Zealand Bloodstock’s 2019 May Sale, but now she is hailing him a genius.

That filly was Sierra Sue and she gave Casey Lock her first taste of Group One success as an owner on Saturday when she won the Gr.1 Futurity Stakes (1400m) at Caulfield for trainers Trent Busuttin and Natalie Young.

The Waikato horsewoman was working in Australia at the time her father purchased the now dual Group One winner, and she said she got the shock of her life when perusing the results on New Zealand Bloodstock’s website.

“I was over in Australia working at the sales and I had a look at the results online and saw Dad had purchased a two-year-old in the tried horse section,” Lock said.

“I rang him and I said ‘what have you done?’

“Looking at it on paper, you think surely someone has tried her or it has problems.

“But I will give it to Dad, if there is anyone out there who can find a good, cheap horse out of the sale, it is him.

“I have gone to the sales with him since I was a little kid and he has never bought anything expensive. He would buy 10 for $1,000 each and he would win with all 10 of them.

“He has got a way of getting the best out of bread-and-butter horses.

“Growing up he has never had anything flash, he has had people’s cast-offs, or horses with problems, and he has been able to work magic with them, and he has done that with this horse.

“She was genuinely untried. He did some homework and found that out. She was a big, heavy filly and from day one she did everything right.”

Lock spent plenty of time with Sierra Sue at her father’s barn and sensed she had plenty of promise early on.

“I took her to her first trial at Cambridge and she got back and flew home. Jasmine Fawcett rode her that day and she said she was pretty special,” Lock said.

“We had to manage her and look after her because she is a big, robust filly and they were pretty firm tracks at the time. We spent a lot of time icing and putting in the extra hard yards with her.

“The day we took her to Te Aroha trials she trialled absolutely impressively, and Phill Cataldo (bloodstock agent) was straight over after the trial.

“Dad turned around and said he had made an offer and I said ‘this is where you make your money – selling them’.”

While Lock said they could be ruing what might have been had they kept her, she said there have been so many positives come out of the sale.

A big one has been major owner Ozzie Kheir gifting Lock and her brother Jamie a one percent share in the mare after he read an article about their love of the horse following her first Group One victory in the Sir Rupert Clarke Stakes (1400m) last spring.

“We love watching her racing over there and winning,” Lock said. “She could have been our next superstar over here, but you can’t look at it like that. You have got to think of the positives.

“Ozzie has come back and bought a very nice Astern filly off Dad, and we were thrilled when he did what he did (gift shares in the mare).

“Dad has been able to do his stables up and he has got state of the art fencing, treadmills, and we are looking are water treadmills now.

“There have been so many positives that have come out of it.”

To add to the weekend, Lock was celebrating her birthday on Saturday and said it was the perfect present to see her mare victorious at Caulfield.

“It was my birthday as well (on Saturday) so it topped off the day,” she said.

“When I trained in partnership with Dad, we won a Great Northern Hurdles and that was pretty cool, but to get my first Group win as an owner was pretty exciting.”

While she is enjoying watching her mare succeed from across the Tasman, Lock said she would love to be trackside herself once COVID-19 enforced border restrictions ease so she can watch her pride and joy compete in the flesh.

“We just love seeing her go so well and hopefully we will be able to get over there soon,” she said.