Iga Swiatek vs the field: Should world No. 1 be the US Open favourite ahead of Simona Halep, Caroline Garcia?

It wasn’t that long ago that it would be unthinkable to tag anyone but Iga Swiatek as favourite for a tournament.

Her 37-match winning streak – the longest on the WTA Tour this century which ended at Wimbledon – featured several moments when it was hard to imagine how she would lose again. It wasn’t just that Swiatek kept on winning, it was that she was winning in such a swashbuckling and confident style. With former world No. 1 Ashleigh Barty retired, it looked like Swiatek was setting herself up as the dominant force on the WTA Tour for years to come.

But four losses later, Swiatek’s position doesn’t look so secure – and the field appears to be closing in ahead of the US Open.

Whether Swiatek remains the favourite depends on how you assess her last six weeks. She had the surprisingly one-sided loss to Alize Cornet at Wimbledon – having had no competitive action on grass ahead of the Grand Slam – and then lost to Caroline Garcia on clay at the Poland Open. In Toronto and Cincinatti she seemed to have rediscovered some form with wins in her opening matches before being bounced out by an in-form Beatriz Haddad Maia and upwardly-trending Madison Keys.

A few numbers stand out from the hard-court defeats: 33 winners vs 28 unforced errors in windy conditions against Haddad Maia, who made just 12 unforced errors; just six winners against 14 unforced errors vs Keys; and, most notably, giving up a combined 33 break-point chances in the two matches. Even the victory over Sloane Stephens in Cincinnati was not entirely clean from Swiatek, who finished with 17 winners to 25 unforced errors.

Swiatek's ball striking, which earlier this season was so smooth, so powerful and looked so easy, now appears a little off. There are more errors than before and not as much assertiveness in rallies.

Perhaps Swiatek's confidence has been knocked a little by her post-Wimbledon results, or perhaps it’s down to the balls used over the North American swing, which are lighter than the ones used on the ATP Tour at this time of the year. The Canadian Open and Western & Southern Open are the only joint ATP-WTA events on the calendar that use different balls, and the same is true of the US Open, which is the only Grand Slam with lighter balls for women than men.

“Honestly, I don’t like them,” Swiatek said after her win over Stephens.

“I’ve heard many players actually complaining as well. Basically the thing is that they’re lighter. They fly like crazy. Right now we play powerful, and we kind of can’t loosen up our hands with these balls…We make more mistakes, for sure...I think those balls are horrible."

Swiatek added that last year she, along with world No. 3 Paula Badosa, spoke to WTA CEO Steve Simon about making changes to the balls. Badosa backed up Swiatek’s comments last week, calling the balls “impossible to control” and saying they are leading to “a lot of errors and a loss of tactics and intelligence on points”.

For Swiatek, harnessing and directing power is one of the keys to her game, and the lighter, hard-to-control balls might be one of the reasons why she is yet to have any success over this stage of the season. While the hard courts of Indian Wells and Miami appeared to her liking earlier this year when she became only the fourth woman to win the Sunshine Double, Swiatek has not made it past the third round in six combined appearances in Toronto/Montreal and Cincinnati.

Aside from the ball complaints, there were also some other snippets from Swiatek in Cincinnati that stood out. Before the tournament she spoke about looking to the future, rather than just the present. “I'm trying to look long term at the whole process and maybe think [where I want to be] in the next season. It's more my team who is kind of like convincing me that I should think long term.” There was also this after her win over Stephens: “I feel like I had ups and downs in terms of practising here. [There are] probably many reasons [for that], but I don’t really want to get into it because I’m trying to really focus on the future.”

Swiatek says she wants to be “fearless again”, an acknowledgement that the freedom she played with during her 37-match winning streak is now not quite the same.

Despite her 'struggles', it’s not difficult to imagine Swiatek regaining confidence after a few wins in New York, rediscovering something near her best form and going deep in the tournament. But there are more doubts than before.

Swiatek is not alone in that department. Few of the top five have shown much form on hard courts this summer and when it comes to picking a winner in New York they may be overlooked in favour of Toronto champion Simona Halep, if she is recovered from her thigh injury, and Cincinnati winner Garcia, who has been in sparkling form over the last two months. Once tipped as a future world No. 1 by Andy Murray, Garcia has soared up the rankings by winning a tour-leading 27 matches since June. She has fired down the most aces this season (286) and is the form pick ahead of the US Open.

World No. 8 Jessica Pegula has not been as spectacular but has had a solid couple of weeks and will be the top-ranked American woman ahead of doubles partner Coco Gauff, who is hoping to be fully fit after an ankle injury. Defending US Open champion Emma Raducanu also showed encouraging signs in dominant wins over former world No.1’s Serena Williams and Victoria Azarenka in Cincinnati before losing to Pegula. And you only need to look down the list of US Open quarter-finalists in the last few years to see that there’s every chance a surprise name makes it deep into the second week.

But will world No. 1 Swiatek still be in the mix at the business end of the tournament? Or will her mini summer slump continue?