Saying goodbye to Montefilia was "very tough and emotional" for part owner Hugh Docherty from Woonona.
The Caulfield and Melbourne Cup runner was sold at the Inglis Chairman's Sale for $3.4 million on Thursday night to Yulong Investments to be a broodmare.
Docherty told the Mercury the decision to sell Montefilia was very difficult but the owners felt it was the best move for the beloved five-year-old.
"It was a tough decision, it wasn't an easy decision because she's such a good animal and we are very close to her and she had done remarkable in her two, three, four and even five-year-old career," he said.
"The partners looked to see how much more she had in her and her overall racing career and thought maybe she's had enough....it was a hard decision but the right one we believe."
Montefilia ran fourth in last year's Caulfield Cup, producing a blistering finish to raise hopes of a Melbourne Cup triumph with Illawarra connections.
However, she settled near last in the great 3200m race and battled to the line for 16th.
Montefilia's four Group 1 wins include the Flight Stakes, Spring Champion, Metropolitan Handicap and Ranvet Stakes took her peak international rating to 115, earning more than $3.2 million in prizemoney.
Docherty admitted it was difficult saying goodbye to Montefilia on Thursday night.
"She's like family to us. It was quite emotional last night saying goodbye," he said.
"Even in the build-up to the sale there was a lot to be done and then when it happens you come back to reality and it hits you hard, she was a special horse for us.
"In saying that I'm happy where she is going. I don't know if they will push on and race with her or send her straight to the paddock to have some foals, that's totally up to them, but wherever it is we will follow her all the way through.
"It's great we've had the opportunity to represent the Illawarra with a horse like her.
"We've got quite a few coming through. It's exciting times ahead still."
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