Women to watch at the Australian Open, where play begins Monday:

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FILE - In this Jan. 9, 2020, file photo, Karolina Pliskova, of the Czech Republic, plays a shot during her match against Ajla Tomljanovic, of Australia, at the Brisbane International tennis tournament in Brisbane, Australia. Pliskova will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020. (AP PhotoTertius Pickard, File)

Women to watch at the Australian Open, where play begins Monday:
FILE - In this Oct. 28, 2019, file photo, Simona Halep, of Romani, eyes on the ball as she plays against Bianca Andreescu, of Canada, during their WTA Finals Tennis Tournament in Shenzhen, China's Guangdong province. Halep will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020. (AP PhotoAndy Wong, File)

Grand Slam Singles Titles: 1 — 1 at French Open (2019)
FILE - In this Oct. 6, 2019, file photo, Naomi Osaka, of Japan, hits a return against Ashleigh Barty, of Australia, during their women's final at the China Open tennis tournament in Beijing. Osaka will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020.(AP PhotoNg Han Guan, File)

Topspin: With her talent and even-keeled demeanor, no reason the locals shouldn't think they could get their first Australian champion since Chris O'Neil in 1978.
FILE - In this July 19, 2019, file photo, Czech Republic's Petra Kvitova returns to Britain's Johanna Konta in a singles match at the Wimbledon Tennis Championships in London. Kvitova will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020. (AP PhotoAlastair Grant, File)

Seeded: 2
FILE - In this Jan. 23, 2019, file photo, Serena Williams makes a forehand return to Karolina Pliskova of the Czech Republic during their quarterfinal match at the Australian Open tennis championships in Melbourne, Australia. Williams will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020.(AP PhotoMark Schiefelbein, File)

Australian Open Career Record: 18-7
FILE - In this Aug. 30, 2019, file photo, Madison Keys chases the ball on a return to Sofia Kenin during the third round of the U.S. Open tennis championships, in New York. Keys will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020.(AP PhotoCharles Krupa, File)

Matchup to Watch For: CoCo Vandeweghe in the 2nd Round
FILE - In this Jan. 18, 2019, file photo, Denmark's Caroline Wozniacki makes a backhand return to Russia's Maria Sharapova during their third round match at the Australian Open tennis championships in Melbourne, Australia. Wozniacki will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020.(AP PhotoKin Cheung, File)

Last 5 Australian Opens: 2019-Won Championship, 2018-4th, 2017-2nd, 2016-3rd, 2015-DNP
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FILE - In this Jan. 9, 2020, file photo, Karolina Pliskova, of the Czech Republic, plays a shot during her match against Ajla Tomljanovic, of Australia, at the Brisbane International tennis tournament in Brisbane, Australia. Pliskova will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020. (AP PhotoTertius Pickard, File)

Women to watch at the Australian Open, where play begins Monday:

FILE - In this Oct. 28, 2019, file photo, Simona Halep, of Romani, eyes on the ball as she plays against Bianca Andreescu, of Canada, during their WTA Finals Tennis Tournament in Shenzhen, China's Guangdong province. Halep will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020. (AP PhotoAndy Wong, File)

Grand Slam Singles Titles: 1 — 1 at French Open (2019)

FILE - In this Oct. 6, 2019, file photo, Naomi Osaka, of Japan, hits a return against Ashleigh Barty, of Australia, during their women's final at the China Open tennis tournament in Beijing. Osaka will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020.(AP PhotoNg Han Guan, File)

Topspin: With her talent and even-keeled demeanor, no reason the locals shouldn't think they could get their first Australian champion since Chris O'Neil in 1978.

FILE - In this July 19, 2019, file photo, Czech Republic's Petra Kvitova returns to Britain's Johanna Konta in a singles match at the Wimbledon Tennis Championships in London. Kvitova will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020. (AP PhotoAlastair Grant, File)

Seeded: 2

FILE - In this Jan. 23, 2019, file photo, Serena Williams makes a forehand return to Karolina Pliskova of the Czech Republic during their quarterfinal match at the Australian Open tennis championships in Melbourne, Australia. Williams will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020.(AP PhotoMark Schiefelbein, File)

Australian Open Career Record: 18-7

FILE - In this Aug. 30, 2019, file photo, Madison Keys chases the ball on a return to Sofia Kenin during the third round of the U.S. Open tennis championships, in New York. Keys will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020.(AP PhotoCharles Krupa, File)

Matchup to Watch For: CoCo Vandeweghe in the 2nd Round

FILE - In this Jan. 18, 2019, file photo, Denmark's Caroline Wozniacki makes a backhand return to Russia's Maria Sharapova during their third round match at the Australian Open tennis championships in Melbourne, Australia. Wozniacki will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020.(AP PhotoKin Cheung, File)

Last 5 Australian Opens: 2019-Won Championship, 2018-4th, 2017-2nd, 2016-3rd, 2015-DNP

Seeded: 1

Country: Australia

Age: 23

2019 Match Record: 57-13

2019 Singles Titles: 4

Career Singles Titles: 7

FILE - In this Jan. 9, 2020, file photo, Karolina Pliskova, of the Czech Republic, plays a shot during her match against Ajla Tomljanovic, of Australia, at the Brisbane International tennis tournament in Brisbane, Australia. Pliskova will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020. (AP PhotoTertius Pickard, File)

FILE - In this Jan. 9, 2020, file photo, Karolina Pliskova, of the Czech Republic, plays a shot during her match against Ajla Tomljanovic, of Australia, at the Brisbane International tennis tournament in Brisbane, Australia. Pliskova will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020. (AP PhotoTertius Pickard, File)

Grand Slam Singles Titles: 1 — 1 at French Open (2019)

Last 5 Australian Opens: 2019-Lost in Quarterfinals, 2018-3rd, 2017-3rd, 2016-Did Not Play, 2015-DNP

Australian Open Career Record: 8-6

Aces: Won 79.7% of service games in 2019; among women playing more than 10 matches, only Serena Williams (80.1%) was better. ... Led WTA in match wins last season.

FILE - In this Oct. 28, 2019, file photo, Simona Halep, of Romani, eyes on the ball as she plays against Bianca Andreescu, of Canada, during their WTA Finals Tennis Tournament in Shenzhen, China's Guangdong province. Halep will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020. (AP PhotoAndy Wong, File)

FILE - In this Oct. 28, 2019, file photo, Simona Halep, of Romani, eyes on the ball as she plays against Bianca Andreescu, of Canada, during their WTA Finals Tennis Tournament in Shenzhen, China's Guangdong province. Halep will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020. (AP PhotoAndy Wong, File)

Topspin: With her talent and even-keeled demeanor, no reason the locals shouldn't think they could get their first Australian champion since Chris O'Neil in 1978.

Matchup to Watch For: Alison Riske in the 4th Round

KAROLINA PLISKOVA

FILE - In this Oct. 6, 2019, file photo, Naomi Osaka, of Japan, hits a return against Ashleigh Barty, of Australia, during their women's final at the China Open tennis tournament in Beijing. Osaka will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020.(AP PhotoNg Han Guan, File)

FILE - In this Oct. 6, 2019, file photo, Naomi Osaka, of Japan, hits a return against Ashleigh Barty, of Australia, during their women's final at the China Open tennis tournament in Beijing. Osaka will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020.(AP PhotoNg Han Guan, File)

Seeded: 2

Country: Czech Republic

Age: 27

2019 Match Record: 52-17

2019 Singles Titles: 4

Career Singles Titles: 16

Grand Slam Singles Titles: 0 — Best: Runner-Up, U.S. Open (2016)

Last 5 Australian Opens: 2019-SF, 2018-QF, 2017-QF, 2016-3rd, 2015-3rd

FILE - In this July 19, 2019, file photo, Czech Republic's Petra Kvitova returns to Britain's Johanna Konta in a singles match at the Wimbledon Tennis Championships in London. Kvitova will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020. (AP PhotoAlastair Grant, File)

FILE - In this July 19, 2019, file photo, Czech Republic's Petra Kvitova returns to Britain's Johanna Konta in a singles match at the Wimbledon Tennis Championships in London. Kvitova will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020. (AP PhotoAlastair Grant, File)

Australian Open Career Record: 18-7

Aces: Has won 10 of her past 12 finals. ... Led tour with 488 aces last season.

Topspin: Might be the best active player yet to win a Grand Slam title and certainly has the skill to change that gap on her resume in Australia.

FILE - In this Jan. 23, 2019, file photo, Serena Williams makes a forehand return to Karolina Pliskova of the Czech Republic during their quarterfinal match at the Australian Open tennis championships in Melbourne, Australia. Williams will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020.(AP PhotoMark Schiefelbein, File)

FILE - In this Jan. 23, 2019, file photo, Serena Williams makes a forehand return to Karolina Pliskova of the Czech Republic during their quarterfinal match at the Australian Open tennis championships in Melbourne, Australia. Williams will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020.(AP PhotoMark Schiefelbein, File)

Matchup to Watch For: CoCo Vandeweghe in the 2nd Round

NAOMI OSAKA

Ranked: 3

Country: Japan

Age: 22

2019 Match Record: 40-11

2019 Singles Titles: 3

Career Singles Titles: 5

Grand Slam Singles Titles: 2 — 1 at Australian Open (2019), 1 at U.S. Open (2018)

FILE - In this Aug. 30, 2019, file photo, Madison Keys chases the ball on a return to Sofia Kenin during the third round of the U.S. Open tennis championships, in New York. Keys will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020.(AP PhotoCharles Krupa, File)

FILE - In this Aug. 30, 2019, file photo, Madison Keys chases the ball on a return to Sofia Kenin during the third round of the U.S. Open tennis championships, in New York. Keys will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020.(AP PhotoCharles Krupa, File)

Last 5 Australian Opens: 2019-Won Championship, 2018-4th, 2017-2nd, 2016-3rd, 2015-DNP

Australian Open Career Record: 13-3

Aces: Entered 2020 with career-best 15 ace total; hit 16 in one match, 18 in another at Brisbane this month. ... Now working with coach Wim Fisette.

FILE - In this Jan. 18, 2019, file photo, Denmark's Caroline Wozniacki makes a backhand return to Russia's Maria Sharapova during their third round match at the Australian Open tennis championships in Melbourne, Australia. Wozniacki will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020.(AP PhotoKin Cheung, File)

FILE - In this Jan. 18, 2019, file photo, Denmark's Caroline Wozniacki makes a backhand return to Russia's Maria Sharapova during their third round match at the Australian Open tennis championships in Melbourne, Australia. Wozniacki will be competing in the Australian Open tennis tournament, beginning Monday, Jan. 20, 2020.(AP PhotoKin Cheung, File)

Topspin: Makes her second title defense at a major; after fourth-round exit at U.S. Open in September, says, "I'm more prepared this time."

Matchup to Watch For: Coco Gauff in the 3rd Round

SIMONA HALEP

Seeded: 4

Country: Romania

Age: 28

2019 Match Record: 43-17

2019 Singles Titles: 1

Career Singles Titles: 19

Grand Slam Singles Titles: 2 — 1 at French Open (2018), 1 at Wimbledon (2019)

Last 5 Australian Opens: 2019-4th, 2018-RU, 2017-1st, 2016-1st, 2015-QF

Australian Open Career Record: 19-9

Aces: Among women playing more than 20 matches in 2019, ranked second on tour by winning 44% of return games. ... Reunited with coach Darren Cahill.

Topspin: Impossible to predict what Halep will do on hard courts or in Melbourne, where she has four 1st-round losses and three quarterfinal-or-better runs in the last eight years.

Matchup to Watch For: Jennifer Brady in the 1st Round, Danielle Collins in the 3rd Round

PETRA KVITOVA

Seeded: 7

Country: Czech Republic

Age: 29

2019 Match Record: 37-16

2019 Singles Titles: 2

Career Singles Titles: 27

Grand Slam Singles Titles: 2 — 2 at Wimbledon (2011, 2014)

Last 5 Australian Opens: 2019-RU, 2018-1st, 2017-DNP, 2016-2nd, 2015-3rd

Australian Open Career Record: 20-10

Aces: Only time past the quarterfinals at any major tournament since 2014 was last year's run to the final in Melbourne.

Topspin: Her flat power worked so well a year ago; if the courts are quick, look out for the lefty.

Matchup to Watch For: Madison Keys in the 4th Round

SERENA WILLIAMS

Seeded: 8

Country: United States

Age: 38

2019 Match Record: 25-6

2019 Singles Titles: 0

Career Singles Titles: 73

Grand Slam Singles Titles: 23 — 7 at Australian Open (2003, 2005, 2007, 2009, 2010, 2015, 2017), 3 at French Open (2002, 2013, 2015), 7 at Wimbledon (2002, 2003, 2009, 2010, 2012, 2015, 2016), 6 at U.S. Open (1999, 2002, 2008, 2012, 2013, 2014)

Last 5 Australian Opens: 2019-QF, 2018-DNP, 2017-W, 2016-RU, 2015-W

Australian Open Career Record: 85-11

Aces: Hadn't won a title of any sort in three years until this month in Auckland. Before that, it was her 2017 Australian Open trophy, giving her 23 at the majors.

Topspin: After taking time off to have a baby, and dealing with a health scare following childbirth, Williams reached two major finals in 2018, then another two in 2019, going 0-4 in the title matches. In Australia a year ago, was a point from reaching the semifinals when an ankle injury derailed her.

Matchup to Watch For: Naomi Osaka in the Quarterfinals

MADISON KEYS

Seeded: 10

Country: United States

Age: 24

2019 Match Record: 28-15

2019 Singles Titles: 2

Career Singles Titles: 5

Grand Slam Singles Titles: 0 — Best, Runner-Up, U.S. Open (2017)

Last 5 Australian Opens: 2019-4th, 2018-QF, 2017-DNP, 2016-4th, 2015-SF

Australian Open Career Record: 18-7

Aces: Won 4 of past 7 matchups against top-5 opponents. ... Run to final at Brisbane shows again she can compete with the best on hard courts.

Topspin: Made first Grand Slam semifinal of her career in Australia and if her big serve and forehand are clicking, could be back to that level.

Matchup to Watch For: Daria Kasatkina in the 1st Round

CAROLINE WOZNIACKI

Unseeded; Ranked: 35

Country: Denmark

Age: 29

2019 Match Record: 20-15

2019 Singles Titles: 0

Career Singles Titles: 30

Grand Slam Singles Titles: 1 — 1 at Australian Open (2018)

Last 5 Australian Opens: 2019-3rd, 2018-W, 2017-3rd, 2016-1st, 2015-2nd

Australian Open Career Record: 34-11

Aces: Playing last tournament of her career. ... Last season was her first without a tour title since 2007.

Topspin: She gets a chance to say goodbye to tennis — and the fans get a chance to say goodbye to her.

Matchup to Watch For: Kristie Ahn in the 1st Round

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