Men to watch at the U.S. Open, which begins Monday:

NOVAK DJOKOVIC

Seeded: 1

Age: 29

Country: Serbia

2016 Match Record: 51-5

2016 Singles Titles: 7

Career Singles Titles: 66

Major Titles: 12 — U.S. Open ('11, '15), Australian Open ('08, '11, '12, '13, '15, '16), French Open ('16), Wimbledon ('11, '14, '15)

Last 5 U.S. Opens: '15-Won Championship, '14-Lost in Semifinals, '13-Lost in Final, '12-F, '11-W

Topspin: Reached the semifinals or better each of the last nine years at Flushing Meadows. Five of the past six, made it to the final, including a second U.S. Open title a year ago. ... Trying to collect three Grand Slam titles in a single season for the third time (2011, 2015). ... Lost in third round at Wimbledon, then first round of Rio Olympics, then pulled out of Cincinnati Masters, citing a sore left wrist.

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ANDY MURRAY

Seeded: 2

Age: 29

Country: Britain

2016 Match Record: 50-7

2016 Singles Titles: 4

Career Singles Titles: 39

Major Titles: 3 — U.S. Open ('12), Wimbledon ('13, '16)

Last 5 U.S. Opens: '15-4th, '14-QF, '13-QF, '12-W, '11-SF

Topspin: Putting together best season of his career, winning Wimbledon and Rio Olympics title (first player with two singles gold medals, let alone two in a row), plus reaching French Open final before losing to Novak Djokovic. ... Will be expected to reverse recent U.S. Open downward trend after collecting first Grand Slam title at Flushing Meadows in 2012. ... His service return and defense are as good as anyone's (with the possible exception of Djokovic). ... Reunited before Wimbledon with coach Ivan Lendl.

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RAFAEL NADAL

Seeded: 4

Age: 30

Country: Spain

2016 Match Record: 34-11

2016 Singles Titles: 2

Career Singles Titles: 69

Major Titles: 14 — U.S. Open ('10, '13), Australian Open ('09), French Open ('05, '06, '07, '08, '10, '11, '12, '13, '14), Wimbledon ('08, '10)

Last 5 U.S. Opens: '15-3rd, '14-Did Not Play, '13-W, '12-DNP, '11-F

Topspin: Sidelined for 2½ months after pulling out of French Open before third round with left wrist injury, but looked good upon return at Rio Olympics, reaching the semifinals in singles and earning a gold medal in doubles with Marc Lopez. ... Seemed to run out of energy at Cincinnati Masters, so biggest question will be what sort of match shape he's in when he gets to New York.

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MARIN CILIC

Seeded: 7

Age: 27

Country: Croatia

2016 Match Record: 32-17

2016 Singles Titles: 1

Career Singles Titles: 15

Major Titles: 1 — U.S. Open ('14)

Last 5 U.S. Opens: '15-SF, '14-W, '13-DNP, '12-QF, '11-3rd

Topspin: Two of his three career Grand Slam semifinal appearances came at Flushing Meadows in 2014 and 2015. ... Coming off a victory over Andy Murray in the final of the Cincinnati Masters hard-court tournament. ... At 6-foot-6 (1.98 meters), equipped with a big serve and flat groundstrokes that translate well on hard courts.

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STEVE JOHNSON

Seeded: 19

Age: 26

Country: United States

2016 Match Record: 26-21

2016 Singles Titles: 1

Career Singles Titles: 1

Major Titles: 0 — Best: 4th Round, Wimbledon ('16)

Last 5 U.S. Opens: '15-1st, '14-1st, '13-1st, '12-3rd, '11-1st

Topspin: Ranked 21st, he's the top American man, one spot ahead of John Isner. ... Earned a bronze in doubles with Jack Sock at Rio Olympics; reached quarterfinals in singles. ... Only 2-5 career record at U.S. Open, only once advancing past first round. ... Won two NCAA individual titles and four team titles in college at Southern California, winning his final 72 singles matches.

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JUAN MARTIN DEL POTRO

Unseeded; Ranked 142nd

Age: 27

Country: Argentina

2016 Match Record: 18-9

2016 Singles Titles: 0

Career Singles Titles: 18

Major Titles: 1 — U.S. Open ('09)

Last 5 U.S. Opens: '15-DNP, '14-DNP, '13-2nd, '12-QF, '11-3rd

Topspin: Silver medal at Rio Olympics, including victories over Novak Djokovic and Rafael Nadal, marked return to elite level after three operations on left wrist. ... Since winning the 2009 U.S. Open, has missed the tournament three of the past six years because of injuries. ... Backhand still a weak point, but his thunderous flat forehand is as good as it gets.

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