NEW YORK, USA - The main draw for the 2019 US Open is out and WTA Insider takes a deeper look at the key storylines in New York. The first round is highlighted by the blockbuster clash between Serena Williams and Maria Sharapova, their first meeting in New York, but beyond the spotlight of that match lies a sea of opportunity for the field. Who will take their chance?

Click here for the full draw. 

This season has seen three different major champions. The first 18 tournaments of the season were won by 18 different women. The two biggest WTA events of the summer hardcourt season were won by players ranked outside the Top 15 and only three players made it to the quarterfinals or better at both Rogers Cup and the Western & Southern Open. All that and both the World No.1 and defending champion as well as the American legend chasing her record-tying 24th major title, come into New York with some health concerns.

There are no sure things this year in New York, far from it. Which is why the 2019 US Open is set to be one of the most exciting and surprising Slams of the season.

TOURNAMENT SNAPSHOT:

Top eight seeds: 1. Naomi Osaka, 2. Ashleigh Barty, 3. Karolina Pliskova, 4. Simona Halep, 5. Elina Svitolina, 6. Petra Kvitova, 7. Kiki Bertens, 8. Serena Williams.

Top half: Osaka, Halep, Kvitova, Bertens
Bottom half: Barty, Pliskova, Svitolina, Serena

Projected Round of 16: Osaka-Bencic, Sabalenka-Bertens, Halep-Andreescu, Stephens-Kvitova, Svitolina-Keys, Konta-Pliskova, Serena-Sevastova, Kerber-Barty. 

Last year's final: Naomi Osaka d. Serena Williams, 6-2, 6-4. 

Serena and Maria meet for the first time at the US Open

The blockbuster first-round match of the tournament landed in the bottom quarter of the draw, as long-time rivals Serena Williams and unseeded Maria Sharapova are set to lock horns for the 22nd time of their careers and the 1st time at the US Open. The statistics around their storied match-up are well known. 

Since defeating Serena to win her maiden major at 2004 Wimbledon and following up that win a few months later at the WTA Finals, Sharapova has not won a match since, losing 18 straight to the American. 

The two last played at the 2016 Australian Open in the Round of 16. They were scheduled to play at the 2018 French Open, but Serena withdrew due to injury. New York will be the site of their first meeting since Serena's return from maternity leave.

When it comes to assessing their recent form, Serena is coming off back-to-back finals, at Wimbledon and the Rogers Cup in Toronto. The 38-year-old had to retire to Bianca Andreescu in the Toronto final due to back spasms and subsequently withdrew from Cincinnati as well. 

After being forced to retire from her first-round Wimbledon match with an arm injury, Sharapova has gradually improved over the hard court summer. She played a high-quality three-setter in a loss to Anett Kontaveit in Toronto, and then defeated Alison Riske in the first round of Cincinnati before losing in straight sets to Ashleigh Barty. 

Naomi Osaka's tough title defense could go through Belinda Bencic

No.1 Naomi Osaka returns to New York with her tennis intact but her questions about her body. Osaka's welcome return to the summer hardcourts resulted in back-to-back quarterfinals in Toronto and Cincinnati, one of only three players to go that deep at both events. 

But Osaka was forced to retire early in the third set against Sofia Kenin in Cincinnati, after picking up a knee injury that left her concerned. Speaking at the draw ceremony on Thursday, Osaka gave a somewhat cagey injury update:

"It’s getting better," Osaka said. "I would say I’m a fast healer so I’m banking on that. 

"I’m here and I feel as healthy as I can be."

Osaka opens her tournament against Anna Blinkova and faces either Astra Sharma or Magda Linette in the second round. The first seed she could face is Carla Suarez Navarro, and looming in the Round of 16 could be No.13 Belinda Bencic, who is 2-0 against Osaka this season, with wins in Indian Wells and Madrid. 

Get through that and one of Kiki Bertens, Aryna Sabalenka, Julia Goerges, Donna Vekic, or Victoria Azarenka could be waiting in the quarterfinals. 

Simona Halep and Bianca Andreescu primed for a Round of 16 clash

No.4 Simona Halep and No.15 seed Bianca Andreescu are the form players in the second quarter of the draw. 19-year-old Andreescu has now won two of the biggest titles of the season at Indian Wells and Toronto, and is coming into New York fully rested and ostensibly healthy. Both women have been drawn into the same section and could meet for the first time in the Round of 16, a match that would surely excite the Romanian fans.

Halep has a manageable path to the Round of 16, opening against a qualifier and then playing either Kateryna Kozlova or a qualifier in the second round, with Wimbledon semifinalist Barbora Strycova looming in the third round. 

Halep has, in many ways, a pressure-free remainder of the season. The reigning Wimbledon champion is ranked No.4, sits at No.2 on the Porsche Race to Shenzhen, and has just 21 points to defend for the rest of the year. Last year, Halep got hit off the court by Kaia Kanepi in the first round of the US Open before ultimately shutting down her season due to back injury.

Andreescu is set to make her US Open main draw debut, having lost in the first round of qualifying in the last two years. The Canadian comes into the tournament at No.8 on the Porsche Race to Shenzhen, and she has made it known that her goals for the rest of the season are to break into the Top 10 and qualify for the Shiseido WTA Finals Shenzhen. Given how she's performed at big tournaments this year, it's hard to count her out. 

Andreescu opens against another teenager, 17-year-old USTA Nationals Champion Katie Volynets, and then would play either Lesia Tsurenko or Mona Barthel. The first seed she could face is Caroline Wozniacki, who is always dangerous, but is just 14-12 on the season so far and lost to Andreescu in Auckland at the start of the season.

Svetlana Kuznetsova remains one to watch in the Halep quarter. 

After her inspired run to the Cincinnati final last week, Kuznetsova could be a real threat in the second week if she can continue her form. Unseeded in New York, Kuznetsova could face 2017 champion Sloane Stephens in the second round, who she beat easily in Cincinnati, and former No.1 Garbiñe Muguruza in the third round, and Petra Kvitova in the Round of 16.

Kuznetsova looks primed to break this section of the draw. 

Victoria Azarenka's bad draw luck continues in New York

Still working to gain traction in her comeback, the former No.1 continues her bad run of luck in the draws. At Wimbledon, she drew Simona Halep in the third round, at the French Open it was Jelena Ostapenko in the first round to play Naomi Osaka, and at the Australian Open, and there was the first-round draw against Serena Williams at Indian Wells. 

This year she's drawn her compatriot, big-hitting Aryna Sabalenka in the first round, with a possible second round against the always tough Yulia Putintseva, and Donna Vekic looming in the third round. 

Karolina Pliskova and Madison Keys target their first majors.

The two best active players who have yet to win a major have both landed in the third quarter of the draw. No.3 Karolina Pliskova and No.10 Madison Keys have had solid summers so far, with Pliskova making the quarterfinals in both Toronto and Cincinnati, and Keys blasting through the field to win the biggest title of her career in Cincinnati. They could face each other in the quarterfinals.

Keys has the tougher draw of the two, potentially having to go through a red-hot Sofia Kenin (against whom Keys is undefeated), with the tough outs of Elina Svitolina, Dayana Yastremska, or Venus Williams looming in the Round of 16.

Pliskova opens against a qualifier and the first seed she can face is Caroline Garcia, who is currently on a 3-match losing streak. The other seeds in her section are French Open finalist Marketa Vondrousova, who is playing her first event since injuring her hand at Wimbledon, and British No.1 Johanna Konta, who is searching for wins after going 0-2 over the hardcourt summer.

Ashleigh Barty has time to play herself into form.

No.2 Ashleigh Barty has spent much of her breakout 2019 season playing high-level tennis. But what she showed over the summer in Toronto and Cincinnati is that she can still go deep at events without anything close to her A-level game. That's a confidence-boosting realization and something the 23-year-old can bank on as she looks to win a second major this season.

While all the spotlight will be on Serena Williams' progression through this bottom quarter, Barty can do what she does best: put on her hard hat and get to work. Prior to this season, Barty's best Slam result came at the US Open last year, where she made the Round of 16. Having won Miami in the spring, Barty has proven she can win on a hardcourt in these conditions.

Barty opens against Zarina Diyas and could face Maria Sakkari in the third round. The Aussie could then face Angelique Kerber, who has not won a match this summer, in the Round of 16, before a potential quarterfinal against Serena if the American can manage her first week. 

Notable First Round Matches: Serena Williams vs. Maria Sharapova, Anastasia Potapova vs. Cori Gauff, Aryna Sabalenka vs. Victoria Azarenka, Svetlana Kuznetsova vs. Kristie Ahn, Aleksandra Krunic vs. Jelena Ostapenko, Garbiñe Muguruza vs. Alison Riske, Andrea Petkovic vs. Mihaela Buzarnescu, Venus Williams vs. Zheng Saisai, Dayana Yastremska vs. Monica Niculescu, Sofia Kenin vs. CoCo Vandeweghe, Johanna Konta vs. Daria Kasatkina, Caroline Garcia vs. Ons Jabeur, Angelique Kerber vs. Kristina Mladenovic, Maria Sakkari vs. Camila Giorgi.