MELBOURNE, Australia – The 2017 Australian Open begins on Monday in Melbourne, with World No.1 and defending champion Angelique Kerber headlining the first night session on Rod Laver Arena. What else do you need to know about your favorite WTA stars as the first Grand Slam tournament of the season gets underway?

1. Kerber contends for first-ever major title defense.
Kerber came away with an impressive haul of Grand Slam titles in 2016, bookending the season with wins Down Under and the US Open – taking the No.1 ranking at the latter. 2017 is a new ballgame for the German, who will seek to defend a major title for the first time in her career. Her first opponent is Lesia Tsurenko, with the likes of Eugenie Bouchard and Roberta Vinci looming in her section of the draw.

2. Serena could reclaim No.1 in Australia.
In the other half of the draw stands 22-time Grand Slam champion Serena Williams, who is firmly in the hunt for her seventh Daphne Akhurst Memorial Trophy in Melbourne. The American would have to reach the final to have a chance at wresting the No.1 ranking from Kerber; click here to find out how it would all have to shake out.

3. Radwanska feeling in Grand Slam rhythm.
Armed with a new racquet, No.3 seed Agnieszka Radwanska is the high seed in Serena’s half of the draw, projecting a rematch of their 2016 semifinal encounter Down Under. Radwanska shrugged off a tough week in Shenzhen to reach the final at the Apia International Sydney, but has a potentially tricky opener against Tsvetana Pironkova. The Bulgarian beat Radwanska in their most recent meeting at last year’s French Open.

4. Halep in hot pursuit of first major title.
No.4 seed Simona Halep also started her year in Shenzhen, but arrived last week for some early preparation in Melbourne on the advice of coach Darren Cahill. The Romanian opens against American Shelby Rogers, and is aiming to build on her pair of quarterfinal appearances earned in 2014 and 2015. 

5. Cibulkova seeking Singapore stepping stone.
No.5 seed Dominika Cibulkova ended 2016 on an all-time high, winning the BNP Paribas WTA Finals Singapore presented by SC Global and reaching a best-ever ranking of No.5. The Slovak’s biggest major success came in Melbourne, where she reached the final back in 2014.

6. Is this Pliskova’s breakthrough moment?
Karolina Pliskova fell before the second week in her first 17 Grand Slam appearances, but made up for lost time in style at the US Open, where she rolled past both Williams sisters en route to the final. The Czech looked just as tough in Brisbane to start 2017, winning the tournament alongside new coach David Kotyza and moving back up to a career-high of No.5.

7. Muguruza feeding off good Melbourne memories.
Garbiñe Muguruza enjoyed a strong start to the season before injury forced her to retire from the Brisbane International semifinals. Still, the the No.7 seed feels fit and fresh ahead of the Australian Open, starting off against New Zealand’s Marina Erakovic on Monday.

8. Kuznetsova rounds out Top 8.
Kuznetsova burned some serious rubber on the Road to Singapore last fall, narrowly qualifying to become the story of the tournament, reaching the semifinals. This year, Kuznetsova is feeling calm as she hopes to surpass the quarterfinals, her previous best finish in Australia.

9. Venus & Serena headline the doubles draw.
The Australian Open women’s doubles draw came out on Sunday, with Wimbledon winners Venus and Serena Williams coming in as the most dangerous floaters in the draw, seeded No.15. The pair could play No.2 seeds Lucie Safarova and new World No.1 Bethanie Mattek-Sands in the third round.

10. No.1 up for grabs in Australia.
The singles No.1 isn’t the only ranking under threat at the Australian Open. Mattek-Sands narrowly took the top spot from Sania Mirza in Brisbane, ending the Indian star’s 91-week reign. But Elena Vesnina and the French team of Caroline Garcia and Kristina Mladenovic all have a shot of taking No.1 during the fortnight. Click here to find out how.