The tennis world is a curious place right now. The 36-year-old Roger Federer is as dominant today as he was back in the 2000s, having spent most of the current decade looking on as others picked up most of the major prizes. Similarly, Rafael Nadal has bounced back and will be the hottest of hot favourites to win the French Open yet again.
By contrast, it is anybody's guess who will pick up the big prizes in women's tennis this year. Ever since Serena Williams won last year's Australian Open while eight weeks pregnant, the competition has been wide open. With the leading tennis player of the last 15 years out of the way, Jelena Ostapenko, Sloane Stephens and now Caroline Wozniacki have all won their maiden Grand Slams, while Garbine Muguruza picked up her second at the Championships, Wimbledon.
With Simona Halep currently world number one without having yet won a Grand Slam - the Australian Open brought her third defeat in a final - it appears anyone's guess who will enjoy the most success in the months ahead.
Serena is easing her way back into action after an extremely tough time giving birth that included a caesarian and life-threatening complications. It remains to be seen if she can recapture her domineering form and fitness. Sister Venus has not been able to fill the gap and nor, so far, has Maria Sharapova.
It all makes the competition seem wide open with the Championships, Wimbledon little more than three months away.
The sheer unpredictability of the current women's game has been epitomised by Sloane Stephens. Just a few weeks before the US Open, she was down at 957th in the WTA rankings after a series of injuries. Widely seen as a player of great potential who never quite fulfilled her promise, she astonished the world by coming through to win in Flushing Meadows.
Since then, however, her form has plummeted just as dramatically. Beset by more injuries, she had not won a single match since her Grand Slam triumph until the Mexico Open, currently taking place in Acapulco. However, after winning two matches to reach the quarter finals, she was beaten 6-4 5-7 6-2 by world number 183 Stefanie Vogele. That means Stephens has lost nine times in 11 matches since her glory night in Flushing Meadows.
With Ostapenko also making little impact of late - her best so far this year was a quarter-final in St Petersburg where she was thrashed 6-0 6-2 by Petra Kvitova - and so many uncertainties about Serena, it seems the women’s game is turning out to be as unpredictable in 2018 as it was in 2017.
All this is without even mentioning Johanna Konta, the Great British hope who has recently started working with Sharapova's former coach Michael Joyce, but has not yet climbed out of her form slump that began last autumn.
The smart money might be on the biggest contests being between Kvitova, Wozniacki and Halep, with Serena maybe re-emerging later in the year. But few would stake too much on this, and the likeliest scenario may be that Wozniacki will not be the only player to secure a maiden Grand Slam this year.
Image: Abbie Parr/Getty Images from Keith Prowse subscription