AP

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

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NOVAK DJOKOVIC

Ranked: 1

Country: Serbia

Age: 31

2018 Match Record: 53-12

2018 Singles Titles: 4

Career Singles Titles: 72

Grand Slam Singles Titles: 14 — Australian Open (2008, 2011, 2012, 2013, 2015, 2016), French Open (2016), Wimbledon (2011, 2014, 2015, 2018), U.S. Open (2011, 2015, 2018)

Last 5 Australian Opens: 2018-Lost in 4th Rd, 2017-2nd Rd, 2016-Won Championship, 2015-W, 2014-QF

Aces: Has won an ATP-best 27.4 percent of his return games against top-10 opponents over his career.

Topspin: Had surgery on his right elbow shortly after last year's early departure in Melbourne and really returned to his best play in the season's second half, winning Wimbledon and the U.S. Open. ... Even if he got off to a slow start to 2019, hard to pick against him getting title No. 7 in Australia.

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RAFAEL NADAL

Ranked: 2

Country: Spain

Age: 32

2018 Match Record: 45-4

2018 Singles Titles: 5

Career Singles Titles: 80

Grand Slam Singles Titles: 17 — Australian Open (2009), French Open (2005, 2006, 2007, 2008, 2010, 2011, 2012, 2013, 2014, 2017, 2018), Wimbledon (2008, 2010), U.S. Open (2010, 2013, 2017)

Last 5 Australian Opens: 2018-QF, 2017-Runner-Up, 2016-1st, 2015-QF, 2014-RU

Aces: Led ATP by winning 36.6 percent of return games in 2018; no one else was even at 31 percent.

Topspin: Pulled out of Brisbane tuneup event, citing a strained thigh muscle, so fitness in Melbourne will be worth keeping an eye on early. ... Hard courts give his body trouble, but if he's OK, could make a deep run at only Slam he hasn't won at least twice.

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ROGER FEDERER

Ranked: 3

Country: Switzerland

Age: 37

2018 Match Record: 48-10

2018 Singles Titles: 4

Career Singles Titles: 99

Grand Slam Singles Titles: 20 — Australian Open (2004, 2006, 2007, 2010, 2017, 2018), French Open (2009), Wimbledon (2003, 2004, 2005, 2006, 2007, 2009, 2012, 2017), U.S. Open (2004, 2005, 2006, 2007, 2008)

Last 5 Australian Opens: 2018-W, 2017-W, 2016-SF, 2015-3rd, 2014-SF

Aces: Will try again for his 100th career title. ... Bids for a third consecutive Australian Open trophy; only Djokovic has done that in the Open era.

Topspin: Everyone keeps wondering how much longer he can keep contending for majors, but still no reason to doubt him.

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ALEXANDER ZVEREV

Ranked: 4

Country: Germany

Age: 21

2018 Match Record: 58-19

2018 Singles Titles: 4

Career Singles Titles: 10

Grand Slam Singles Titles: 0 — Best: QF, French Open (2018)

Last 5 Australian Opens: 2018-3rd, 2017-3rd, 2016-1st, 2015-Did Not Play, 2014-DNP

Aces: Now working with Ivan Lendl, an eight-time major champ as a player and former coach of Andy Murray. ... Only 44th-best at saving break points last season, doing so just 58 percent of the time.

Topspin: Supremely talented, but biggest impediment to reaching the last weekend of a major seems to be health; pulled out of tuneup in Adelaide after hurting a hamstring in practice.

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KEVIN ANDERSON

Ranked: 6

Country: South Africa

Age: 32

2018 Match Record: 47-19

2018 Singles Titles: 2

Career Singles Titles: 6

Grand Slam Singles Titles: 0 — Best: RU, U.S. Open (2017), Wimbledon (2018)

Last 5 Australian Opens: 2018-1st, 2017-DNP, 2016-1st, 2015-4th, 2014-4th

Aces: At 6-foot-8 (2.03 meters), can deliver dangerous serves with the best of them. His 1,082 aces ranked second on tour in 2018.

Topspin: Seemingly has a game built for success in Melbourne, but hasn't won a match there in four years. With confidence built from runs to finals at two of the past five majors, could he be ready to do some damage at this one?

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DOMINIC THIEM

Ranked: 8

Country: Austria

Age: 25

2018 Match Record: 54-20

2018 Singles Titles: 3

Career Singles Titles: 11

Grand Slam Singles Titles: 0 — Best: RU, French Open (2018)

Last 5 Australian Opens: 2018-4th, 2017-4th, 2016-3rd, 2015-1st, 2014-2nd

Aces: Only two career titles have come on hard courts; eight on clay, where he managed to beat Nadal last year and also reached his first major final.

Topspin: A physical presence on court who can bully an opponent during baseline exchanges, certainly capable of sticking around into the second week in Australia.

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KEI NISHIKORI

Ranked: 9

Country: Japan

Age: 29

2018 Match Record: 43-21

2018 Singles Titles: 0

Career Singles Titles: 12

Grand Slam Singles Titles: 0 — Best: RU, U.S. Open (2014)

Last 5 Australian Opens: 2018-DNP, 2017-4th, 2016-QF, 2015-QF, 2014-4th

Aces: Held in 81.4 percent of his service games last season, the lowest rate of any member of the year-end top 10.

Topspin: If the bracket breaks in his favor, could make a deep run. Past four exits in Melbourne came against Federer, Djokovic, Nadal and Wawrinka, who've all won the tournament.

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JOHN ISNER

Ranked: 10

Country: United States

Age: 33

2018 Match Record: 34-22

2018 Singles Titles: 2

Career Singles Titles: 14

Grand Slam Singles Titles: 0 — Best: SF, Wimbledon (2018)

Last 5 Australian Opens: 2018-1st, 2017-2nd, 2016-4th, 2015-3rd, 2014-1st

Aces: Led ATP last year by winning 93.6 percent of his service games. ... Led tour with 1,213 aces in 2018.

Topspin: After quick exit in Australia, wound up having best season of career in 2018; maybe he channels last year's Grand Slam success at Wimbledon, U.S. Open and making his first quarterfinal in Melbourne.

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STEFANOS TSISIPAS

Ranked: 15

Country: Greece

Age: 20

2018 Match Record: 46-27

2018 Singles Titles: 1

Career Singles Titles: 1

Grand Slam Singles Titles: 0 — Best: 4th, Wimbledon ('18)

Last 5 Australian Opens: 2018-1st, 2017-DNP, 2016-DNP, 2015-DNP, 2014-DNP

Aces: Will be making just his seventh career appearance in the main draw of a major tournament. ... One of the brightest young up-and-coming stars on tour.

Topspin: A terrific mover at 6-foot-4 (1.93 meters), uses a big forehand and good hands at the net. Probably needs to improve his serve to take the next step into the top 10.

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NICK KYRGIOS

Ranked: 51

Country: Australia

Age: 23

2018 Match Record: 25-13

2018 Singles Titles: 1

Career Singles Titles: 4

Grand Slam Singles Titles: 0 — Best: QF, Australian Open ('15), Wimbledon ('14)

Last 5 Australian Opens: 2018-4th, 2017-2nd, 2016-3rd, 2015-QF, 2014-2nd

Aces: 44 aces in match at Brisbane to open year, only one shy of record for an ATP three-setter. ... Averaged 19.8 aces per match last season.

Topspin: As talented and mercurial as they come, as liable to beat one of the Big 3 in the second week as he is to bow out in the early rounds.

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Follow Howard Fendrich on Twitter at http://twitter.com/HowardFendrich

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