Global racing giant Godolphin stands between Winx and a record fourth Cox Plate after international star Benbatl pushed the course record at Caulfield when claiming the Group 1 Caulfield Stakes in spectacular style.
But the challenge not only comes from trainer Saeed bin Suroor's galloper Benbatl, who made it three G1 wins in a row following two such successes in Germany, as he held a narrow margin on the line over another Godolphin galloper, Blair House, who is prepared by Charlie Appleby.
Benbatl's time of 2:00.84 recorded for the 2000-metre trip was just half a second outside the course record. Starting at $9 after opening at $6, Benbatl won by a half-head from the fast-finishing Blair House ($12), with two-and-a-quarter lengths to Humidor ($6) in third place.
Saeed bin Suroor said after the race that Benbatl was the best horse he has brought out to Australia in the 20 years since he first came to Melbourne, but stopped short of claiming that he could finally be the undoing of Winx, who has won 28 races in a row.
"I have the target (of the Cox Plate) for him in January when he was still in Dubai," bin Suroor explained.
"But the superstar Winx is in the race. It's hard to beat her. She's the best of the best.
"He's the best horse we've bought out. He's a class horse.
"We've bought out some horses for the Melbourne Cup in the past. Unlucky for some of them they didn't stay sound but this one he's got class and he's got speed."
Blair House (IRE) and James Doyle cannot quite reach Benbatl (GB) and Pat Crosgrove, picture Quentinjlang.com
Bin Suroor said Winx loomed as a huge obstacle for his horse but he said horse racing was never totally predictable.
"It's racing. But she's a super star. I have a lot of respect for her," he added.
For jockey Pat Cosgrave, he will always remember his first ride in Australia.
"He's a high-class horse," he said of Benbatl. "I was surprised he was such a big price and the first and second are two very good horses.
"It's a hell of a training performance. He's a top-class horse, that's his third Group 1, and I've not ridden him since he was third in the Dante. I think he's a nine-or-10-furlong specialist.
"Oisin Murphy picked up the ride since I was last on him and I'm here to ride Best Solution in the Caulfield Cup next week but I think the plan is for Oisin to ride him in the Cox Plate.
"He couldn't make it this week and I was glad I could step in and if he's not then I'll be here.
"Winx is a great mare, I probably don't want the (Cox Plate) ride as if he did win I'd probably be escorted out the country pretty quick.
"It's going to be a fascinating race and I'd say he'll need to come forward from today as he lacked a bit of sharpness, but the ground was probably a little bit fast for him. He'd appreciate a bit more give in the ground, but he'll have to be on his A-game that's for sure."
James Doyle said Blair House had improved sharply from his first-up run in Australia when fourth in the Underwood Stakes.
"It's frustrating," he said. "I shouldn't be. I had a perfect trip round and Benbatl's a good horse. They're both tough horses.
"He's run a cracker. I got a lovely position following Benbatl, which helped. I served it up to him, but he's a very tough horse."
Humidor, who pushed Winx in last year's Cox Plate, was no match for the two raiders in third place and just behind him was another international in the form of the Aidan O'Brien-trained The Cliffsofmoher.
It was a similar run to last year of another former Coolmore horse, Johannes Vermeer, who debuted Down Under with a second placing in the Caulfield Stakes before backing up seven days later to run third in the Caulfield Cup before 17 days after that running second in the Melbourne Cup.
The Cliffsofmoher is understood to be taking the same path this spring.
Caulfield Stakes, photo finish picture Racing.com