A year ago, Italy’s Flavia Pennetta shocked the tennis world by winning the US Open and promptly announcing her retirement. This year, the defending champion on the women’s side will be conspicuous in her absence. But even she had been in the draw, no one, not even her new husband, tennis player Fabio Fognini, would have put their money on a repeat performance. In the past year, women’s tennis has been delightfully unpredictable. This trend, which seemed to have been somewhat bucked by Serena Williams’s victory at Wimbledon this July, is likely to resume on Monday. For the first time in quite a while, Williams will not go into a Grand Slam as the favorite.

This summer, Williams has suffered woes very similar to those of her male counterpart, Novak Djokovic. Since her historic win at Wimbledon, where she equalled Steffi Graf’s Open Era record of 22 slams, Williams has been hampered by a sore right shoulder. She lost in the third round in singles in Rio, but what was even more shocking was that she and sister Venus crashed out in the first round of the doubles competition. Williams pulled out of both Montreal and Cincinnati, and has basically played just three matches since Wimbledon. What she recently said about her game echoes Djokovic’s sentiments: "I have not played a lot, I haven't practiced a lot, but I'm just now starting to feel a little better. Hopefully just every day I will keep going higher."

Tough road for Serena

Williams comes to New York in search of a record 23rd title. But rusty as she is, she will have a tough contest in the very first round, where she plays two-time Grand Slam semi-finalist Ekaterina Makarova of Russia. It could be a very tricky match for the American. If she survives, she might meet 2011 US Open champion Sam Stosur in the fourth round, and then last year’s semi-finalist Simona Halep of Romania in the quarter-final. Halep, one of the handful players who comes into this event high on confidence, poses the most serious threat. Seeded fifth, Halep had an excellent US Open Series, winning back to back tournaments in Bucharest and Montreal. In fact, she won 13 straight matches before finally losing in the semis in Cincinnati.

Two other players who did very well in the US Open Series on the women’s side are winner Agnieszka Radwanska of Poland and Johanna Konta of Great Britain, both of whom tied the series at 220 points each. Radwanska won the Connecticut Open this weekend, and reached the quarter-finals in Cincinnati and the fourth round in Montreal, while Konta won the Bank of the West Classic in Stanford and reached the quarter-finals in Montreal and the fourth round in Cincinnati. But it was Radwanska who edged out Konta to win the series overall because of her head-to-head result over the British woman. Joining Halep, Radwanska, and Konta in excellent form coming into New York is Czech woman Karolina Pliskova, who won Cincinnati last week.

In the bottom half, the two players to watch are the two who have beaten Serena Williams in Grand Slam finals this year. Australian Open champion Angelique Kerber of Germany is closing in on Serena’s No. 1 ranking. She had a chance to take over as the new No. 1 in Cincinnati, until she lost in the final to Pliskova. Kerber will have another shot at the Open. But she has a pretty tough draw, scheduled to meet Sara Errani in round three, two-time Wimbledon champion Petra Kvitova in round four, and this year’s French Open champion and world No. 3 Gabine Muguruza in the semis. Muguruza has had a dismal season ever since she won the French Open, which is not unusual for a first-time Grand Slam champ. If, however, she does manage to fulfill her seeding potential and reach the semi-final, her match with Kerber could be a fantastic one.

Unpredictable draw

There are usually a few other stories to watch for in New York, besides who will actually win the title. This year should be no different. For instance, there are the veteran on the way out and the newest star of women’s tennis. On the one hand, Venus Williams, now 36, is surely facing the twilight of her remarkable career. Inspired by the home crowd who will root for her vociferously, the American might just enjoy her last solid performance at a major in New York. But, it will be very difficult for her to get past Pliskova in the fourth round. One the other hand, 22-year-old Monica Puig, who got the final seeding at the US Open when American Sloane Stephens withdrew, is the brand new Olympic women’s singles champion. In Rio, she beat three grand slam champions – Muguruza, Kvitova, and Kerber – on the way to the gold medal, thus securing Puerto Rico’s first ever Olympic medal in the process. Could the surprise win catapult her to the top level of the women’s game? Last week, she made it quite clear that her season was not over, when she said about the US Open, “I’m here and I’m ready to go.”

And so are we. It is really impossible to predict who will win the title on the women’s side. Will it be a veteran overcoming physical odds, or a first-time champion like we have already seen twice this year? Will we have a new No. 1 by the end of the tournament? Only one thing is certain. Women’s tennis has never had these many contenders for a Grand Slam title.

Oindrila Mukherjee tweets here.