Twenty-eight wins in a row, but not everyone is convinced Winx is a great . . .

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On Saturday the world will be watching as Australia's superstar Winx bids to win the prestigious Cox Plate for a fourth consecutive year. The seven-year-old is believed by many to be one of the greatest horses of all time but others, including ITV's Matt Chapman, have questioned her quality and the level of opposition she has faced. So just how good is Winx? Is she a good horse made to look brilliant by where she races, or is she really a supermare without compare?

What has she won?

Brigadier Gerard won 14 Group 1 races, Frankel landed ten and Sea The Stars scored six times against the best but Winx has an almighty 21 top-level wins on her CV. Her most memorable successes have been in the Cox Plate, one of Australia's biggest races.

It was her second of three Cox Plate wins that established her as something very special. Fears grew that her unbeaten streak would be ended by the sharply improving Hartnell in 2016 but she toppled the Godolphin challenger with a stunning eight-length victory.

The Chris Waller-trained mare has enjoyed a remarkable 28 consecutive wins, from six and a half furlongs up to a mile and a quarter, carrying big weights in handicaps, on a variety of going conditions and winning the majority with ease.

Australians have fallen in love with her, she has promoted the sport globally and has become one of the most prolific top-level winners in history.

Who has she beaten?

The biggest question mark over Winx concerns the calibre of horses she has beaten.

Winx's first two Cox Plate wins offer a strong depth of international form to analyse.

In her initial Plate success in 2015 she registered what remains the strongest piece of European form in beating Highland Reel.

Aidan O'Brien's globetrotter was not at his best until the following season, but he was already a Group 1 winner going to Moonee Valley, where he proved no match for Winx, finishing a five-and-a- half-length third behind the burgeoning star.

Considering he won the Hong Kong Cup on his next start, that form is unquestionably brilliant.

The aforementioned Hartnell had a career-best Group 3 win in Britain, but flourished when based in Australia. He clearly improved for the switch and demolished a Group 1 field himself before that 2016 defeat in the Cox Plate.

Winx won last year's Plate by half a length from Humidor, with third-placed Folkswood, trained by Charlie Appleby, four and three-quarter lengths further back.

Before heading to Australia, Folkswood's best run was a neck second in the Group 1 Jebel Hatta in Dubai to Decorated Knight, an established top-class performer in Britain and Ireland. Folkswood has never quite sparkled since that second, but, as others have encountered, he was no match for the great Winx.

To be critical, the form of the last two Cox Plates has not been anything particularly special. Winx has beaten decent Group-level horses but we have not really seen her take on anything of high-class quality and the same applies for the races she has been in this year.

A final point to keep in mind regarding the European challenge to Winx. If you owned a talented horse, would you miss an abundance of potential Group races in Europe to go through quarantine, travel and take on a mare who has looked impossible to beat? Maybe Winx has scared off her European challengers.

How well did she beat them?

Winx has a distinctive and exciting running style, holding a midfield position and slowly creeping up to the principals before kicking clear.

It is as if she has another extra gear as she enters the final furlong and she quickens further to reach the line. The remarkable thing about that final-furlong turn of foot is that sometimes she is a few lengths clear already.

Her wins are not always dominant and stress-free, and in fact there have been plenty of times this year when it has looked like her sequence is set to be scuppered, before she quickens and eradicates such doubts.

In football, the teams that win the big titles are not always the ones who play the best, it is the teams who find a way to win. Just like Winx.

What do the ratings suggest?

The official ratings would suggest that she is the joint-best horse in the world at the moment, sharing a rating of 130 with Saturday's impressive Champion Stakes winner Cracksman. But the John Gosden-trained star posted a joint career-best Racing Post Rating of 131, and Winx's best RPR has been 130, which she achieved in her 2016 Cox Plate and 2017 George Ryder Stakes win.

The verdict from Sam Walker, Racing Post Ratings analysist

With a 28-race winning run you can't knock Winx for her reliability and longevity, but you can definitely pick holes in a lot of her form.

The truth is that on her day – like when she won the 2016 Cox Plate by eight lengths – she is one of the best in the world and has the RPRs to back it up, but most of the time she doesn't need to be anywhere near her best because her opposition is limited.

Cracksman: The world's highest rated horse following another Champion Stakes demolitionCredit: Charlie Crowhurst

The problem with her being so far superior to her rivals is it's hard to gauge what sort of form she is in at any time. At her best she has RPRs of 130, putting her broadly on a par with this year's world leader Cracksman (131), but in 2018, despite continuing to win, her best RPR is just 122 and her average is 116.

If she can run to this year's best form in the Cox Plate it should be enough to see off Benbatl, who ran to a mark of 117 last time and has to concede 2kg (4.4lb).

How big a danger is Benbatl?

This year's leading British challenger in the Cox Plate, Benbatl, appears to be her strongest rival yet. To compare the form with fellow Godolphin's former Cox Plate hope Folkswood, Benbatl was a convincing three and-a-quarter-length winner in Dubai and furthermore has landed another Group 1 in a prep run in Australia.

The pace of the race could suit Benbatl's running style. He runs from a handy position, goes for home quite early but seems to be a strong battler all the way to the line, and there is no doubting Oisin Murphy will have the confidence to stick to his game plan.

Benbatl: Hoping to break Winx's unbeaten record on SaturdayCredit: Tom Dulat

Hugh Bowman will need to be sure not to time his run too late or get stuck behind runners.

Aussie rules?

This time last year there was talk of Winx coming to Royal Ascot, but that never got off the ground with a fourth tilt at the Cox Plate the prime objective.

That makes it extremely difficult to assess her versatility in terms of racing in a different environment. Fellow Aussie legend Black Caviar did make a winning visit to Ascot in the Diamond Jubilee Stakes, but that nearly went disastrously wrong with her jockey easing up before the line and it was hard to judge the mare on it.

Black Caviar: Aussie superstar made a winning visit to Royal Ascot in 2012Credit: Edward Whitaker

We all crave to see top horses take on one another and, rightly, travelling to take on the best overseas is considered the supreme test.

As such, it is a huge shame Winx has never raced outside Australia. But that does not necessarily detract from her achievements – don't forget that Frankel never raced outside Britain.

The Winx conclusion

A personal view is that Winx as one of the greatest racehorses of all time. Some of the races she has won have been weak Group 1s and sometimes she has had to scramble home, but she has still won, and that is the sign of a true champion. To rack up 28 consecutive wins over varying distances shows supreme class and consistency.

Winx and Hugh Bowman are given a champion's welcome after second Cox Plate winCredit: Vince Caligiuri (Getty Images)

The Aussie Angle

The thoughts of Winx from Australian racing journalist Carl Di Iorio:
In the last 15 years Australians have been spoiled by witnessing probably three of the best mares ever to race in this country. Makybe Diva won seven Group 1s, including a Cox Plate and three consecutive Melbourne Cups, then Black Caviar came along, unbeaten from 25 starts and winner of 15 Group 1s.

Winx has combined the best of both those mares, an amazing winning streak coupled with longevity at the highest level.

The opposition she has faced has been moderate at times but that does not diminish her legacy and trainer Chris Waller’s excellent management. Australians love their racing and unanimously adore Winx and what she has achieved. Pictures of Winx are all over the newspapers, front and back pages.

There is always the expectation Winx will win, but her racing style lends itself to suspense. There have been several times where she has looked vulnerable, only for you to feel foolish for having doubts a few seconds later. That adds to her legend.

She has managed to get so many people emotionally involved, which is great. It shows there is more to racing than just betting outcomes.

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