Dogs make the best people. And racehorses make the best sportspeople.

Racehorses don't go to Bali and take something they shouldn't. The integrity unit doesn't have a racehorse's mobile phone on speed dial. A racehorse doesn't post on social media inappropriate videos of it doing lurid things with other racehorses watching.

No, racehorses don't hold out for more money. They don't sneer at the crowd. They never refuse an autograph. The only time racehorses become problematic is when people get involved.

The best sportsperson in Australia right now is Winx, and after her demolition in the Cox Plate at Moonee Valley last Saturday she surpasses Black Caviar as the superior racehorse.

There, I said it.

Earlier this year, I spoke to Winx's trainer, the smiling assassin that is Chris Waller, about his mare and the prospect of winning a second Cox Plate, which is still the race every trainer covets more than any other race, including the Melbourne Cup.

The best horses win the Cox Plate. Winx has two. Some bookies are already offering as much as $3.80 to make it three. Climb on board because you are unlikely to get that price again in Winx's racing career.

In the autumn, Waller and the horse's connections had one eye on the weather and the problematic Randwick track when they decided to run in the Doncaster Mile on the first day of the Championships instead of the Queen Elizabeth Stakes on the second day a week later.

With jockey Hugh Bowman on board, Winx threaded the needle through a wall of horseflesh in front of her after being blocked for a run on the turn. She won easily.

That race, though, took so much out of Winx, more than Waller really let on publicly.

But, during the horse's time in the paddock, he saw her improve. She got better.

"I've only read about it when trainers talk about their great horses," he said to me in an interview in July. "They say their horse is coming back bigger and stronger. And I usually think, 'Yeah whatever. How can they get better?' Well, I'm going to say it: she's come back bigger and stronger. She's taller, she's not in big condition, she's in perfect condition, which is 15 kilograms heavier than before."

He then plotted a defence of the Cox Plate that started with races in Sydney and ended in group 1s in Melbourne. It was exactly the same program the great Kingston Town had taken in 1981 to claim the second of his three Cox Plates.

We all tumbled into the idea of a race between the John O'Shea-trained Hartnell and Winx. When you think about it with hindsight, it was wishful thinking.

Hartnell's recent form has been great – and he is rightly the favourite for the Melbourne Cup – but he is not in the same class as Winx.

At the 800 metres in the Cox Plate, as the two horses broke away, it looked like we were about to watch a replay of 1986 when Bonecrusher and Our Waverley Star slugged it out down the straight.

At the turn, though, it looked more like a procession. Winx broke clear, Bowman flicked her with his whip, the mare flicked her mane … and she won by eight lengths.

Like many, I backed Hartnell, just for the sake of it. I thought the $3.70 on offer was too tantalising to ignore for a horse of that quality. I've never been so happy to drop money on a race in my life.

With Winx now one of the all-time greats, the question invariably becomes … just how great?

Comparing racehorses is about as tricky as comparing footballers and cricketers. You can compare prizemoney and Timeform ratings and group 1s conquered and, of course, the fact that Black Caviar was unbeaten in 25 starts.

It's a silly little bar room argument because Black Caviar was a sprinter, best suited to 1000m or 1200m, and Winx a middle-distance speciality, especially over 2000m.

But you can admire.

I can already hear the sound of angry fingers bashing keyboards, but for mine Winx is a standout. She's won over distances from 1300m to 2040m, in weight-for-age and handicap conditions, from sitting on the pace, from coming from the rear of the pack, sometimes coming right through it.

Waller has taken a conservative approach with her in the last couple of preparations, and it would stun all concerned if he ran her over two miles in the Melbourne Cup.

Some horses never recover when racing over that distance for the first time. Winx has many more races to win, she will go well beyond $10 million in prizemoney, and a tilt at the Cup could gas her.

But what a thought. Winx, coming off a second Cox Plate, trying to join some of the true greats in snaring the Cox Plate-Melbourne Cup double.

Waller has said it a few times that he expects Winx to be beaten at some stage. The question, though, is obvious … Um, when?

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