The second half of the Sunshine Double is about to begin; what are the biggest storylines heading into the two weeks in Miami?
WTA Staff

MIAMI, FL, USA - The dust has barely settled after a fortnight in Indian Wells when all eyes turn to South Florida as the Miami Open kicks off on Tuesday.

Here are 10 things to know before the year's second Premier Mandatory event:

1. All eyes on are on top seed Angelique Kerber.
Angelique Kerber will enter Miami as the No.1 seed for the first time in her career.

The top seed has won the title here 13 times, most recently in 2015 when Serena Williams defeated No.12 seed Carla Suárez Navarro in the final.

2. The World No.1 ranking is secure - for now.
After Williams' withdrawal from the BNP Paribas Open and Miami Open, Kerber returned to the top of the WTA rankings. This fortnight will be Angelique Kerber's 21st and 22nd weeks at World No.1 - surpassing Kim Clijsters (20 weeks), Tracy Austin (21 weeks) and Maria Sharapova (21 weeks) in terms of all-time weeks atop the WTA rankings. And with Williams absent, she cannot be usurped at the end of the tournament, regardless of results.

3. Mouthwatering matchups headline the first and second round.
With 17 of the WTA's Top 20 - and 46 of the Top 50 - in action at the Miami Open, it's no surprise that we'll be seeing some big clashes right away.

Notable first round matches:
Eugenie Bouchard vs. Ashleigh Barty
Belinda Bencic vs. Sara Errani
CiCi Bellis vs. Ajla Tomljanovic
Jelena Jankovic vs. Yaroslava Shvedova

Notable second round matches:
Angelique Kerber vs. Laura Siegemund
Svetlana Kuznetsova vs. Kristyna Pliskova
Agnieszka Radwanska vs. Wang Qiang
Jelena Ostapenko vs. Karolina Pliskova

Click here for WTA Insider's full analysis of the Miami draw.

4. We might see a new Miami Open champion.
Victoria Azarenka defeated Svetlana Kuznetsova in the 2016 final, but due to the birth of her son Leo in December 2016 the Belarusian is not in Miami to defend her title. And with the eight-time champion Williams out, the field in Miami is wide open. Will we will see a brand new Miami Open champion, or will former champions Agnieszka Radwanska (2012) or Svetlana Kuznetsova (2006) go for a second title?

5. The depth of American tennis is in full display.
The United States is the best represented country at the Miami Open this year, with 13 main draw players in contention. Among them: the youngest player in the main draw, Amanda Anisimova, (15 years old) and the oldest, Venus Williams (36 years old).

6. Time for Madison Keys to shine?
Speaking of talented Americans, Madison Keys made her return from injury at the BNP Paribas Open where she posted a solid run to the fourth round. Despite playing just three matches in her relatively brief return, the American answered many questions about her form and put together dominating performances against Mariana Duque-Mariño and Naomi Osaka before falling to an in-form Caroline Wozniacki. Can the American go even further in her home tournament?

7. Sunshine Double in sight for Vesnina?
Elena Vesnina surprised the world when she stormed to her biggest career title at the BNP Paribas Open, beating Angelique Kerber, Venus Williams, Kristina Mladenovic, and Svetlana Kuznetsova along the way. Now she's got a new challenge ahead: claiming the Sunshine Double.

Last year, Azarenka became just the third player to win at both Indian Wells and Miami in the same year, after Stefanie Graf (1994, 1996) and Kim Clijsters (2005). Can Vesnina add her name to the list?

8. Next Gen wildcards ready to make their mark.
The Miami Open draw boasts a diverse set of main draw and qualifying wildcards, including Kuala Lumpur champion Ashleigh Barty and St. Petersburg semifinalist Natalia Vikhlyantseva. Another wildcard to watch out for is 15-year-old American Amanda Anisimova. A junior standout, Anisimova reached the final of last year's French Open and nearly qualified for the senior-level main draw at the US Open.

9) Full circle for Spain?
Garbiñe Muguruza first captured international attention in Miami, reaching the fourth round as a wildcard back in 2012. Carla Suárez Navarro went even farther in 2015, reaching the final before falling to Williams.

Muguruza comes to Miami after a narrow loss to Karolina Pliskova last week. The Spaniard also snapped Elina Svitolina's 15-match winning streak en route to the quarterfinals, and will likely face more surging opposition in the fourth round in the form of No.12 seed Caroline Wozniacki. For Suárez Navarro, a potential fourth-round clash with Kerber looms in the draw.

10) Here's where you can tune in.
Miami Open qualifying wraps up on Tuesday, March 21 with main draw play beginning the same day.

Click here to select your country and tune into the Miami Open.