Western and Southern Open 2018: Novak Djokovic, Sloane Stephens Advance

Defending champion Garbine Muguruza headlines the list of stars in action Wednesday in Mason, Ohio, at the 2018 Western & Southern Open.

Muguruza will get her title defense underway against Lesia Tsurenko in the second round.

Men's champion Grigor Dimitrov will be stepping on the court for the first time as well for a matchup with Mischa Zverev. Dimitrov will be looking to rebound after a first-round exit at Wimbledon and then a straight-sets defeat to Kevin Anderson in the third round of the Rogers Cup.

Fans will have no shortage of big names to watch Wednesday, with Novak Djokovic, Simona Halep, Sloane Stephens and Juan Martin del Potro also playing in the second round. The full schedule for the tournament is available on the Western & Southern Open's official site.

Here's a look at the scores throughout the day and a recap of the biggest matches.

Men's Singles Results

Robin Haase def. No. 3 Alexander Zverev: 5-7, 6-4, 7-5

No. 5 Grigor Dimitrov def. Mischa Zverev: 7-6(5), 7-5

No. 6 Kevin Anderson def. Jeremy Chardy: 7-6(6), 6-2

No. 7 Marin Cilic def. Marius Copil: 6-7(4), 6-4, 6-4

No. 10 Novak Djokovic def. Adrian Mannarino: 4-6, 6-2, 6-1

No. 11 David Goffin def. Benoit Paire: 5-7, 6-4, 6-2

No. 13 Pablo Carreno Busta def. Bradley Klahn: 6-4, 6-4

No. 15 Nick Kyrgios def. Borna Coric: 7-6, 0-6, 6-3

Milos Raonic def. Malek Jaziri: 6-3, 7-5

Karen Khachanov def. Sam Querrey: 7-5, 6-4

Stanislas Wawrinka def. Kei Nishikori: 6-4, 6-4

Marton Fucsovics def. Guillermo Garcia-Lopez: 6-7(5), 6-4, 7-5

No. 4 Juan Martin del Potro vs. Hyeon Chung (suspended)

Women's Singles Results

Kiki Bertens def. No. 2 Caroline Wozniacki: 6-4, 0-0 (retired)

No. 3 Sloane Stephens def. Tatjana Maria: 6-3, 6-2

No. 4 Angelique Kerber def. Anastasia Pavlyuchenkova: 4-6, 7-5, 6-4

Lesia Tsurenko def. No. 7 Garbine Muguruza: 2-6, 6-4, 6-4

Aryna Sabalenka def. No. 9 Karolina Pliskova: 2-6, 6-3, 7-5

No. 13 Madison Keys def. Camila Giorgi: 6-2, 6-2

No. 15 Elise Mertens def. Rebecca Peterson: 3-6, 6-2, 7-6(1)

No. 16 Ashleigh Barty def. Kaia Kanepi: 7-5, 6-3

Ekaterina Makarova def. Alize Cornet: 6-2, 6-0

Anett Kontaveit def. Maria Sakkari: 6-1, 6-3

Angelique Kerber def. Anastasia Pavlyuchenkova: 4-6, 7-5, 6-4

No. 1 Simona Halep vs. Ajila Tomljanovic: 4-6, 6-3, 4-3 (suspended)

Amanda Anisimova vs. Petra Martic: 5-4 (suspended)     

Notable Matches

No. 3 Sloane Stephens def. Tatjana Maria: 6-3, 6-2

Stephens made quick work of Tatjana Maria, winning in straight sets.

Maria had her moments, including a backhand passing shot that elicited acknowledgment from Stephens:

But the 31-year-old German ultimately couldn't solve Stephens' serve. The 2017 U.S. Open champion won 79 percent of her first-service points and 67 second-service points. Stephens used her serve excellently to set up the rest of her game.

She was aggressive with her return game as well, which helped her earn five service breaks.

While beating Maria may not seem like a big result, Stephens lost in the opening round of Wimbledon and then exited in the second round of the Citi Open.

Much like her run to the Rogers Cup final, Wednesday's match was another example of how unstoppable Stephens can be when she's in top form. Such a commanding performance sets her up well for the rest of the tournament.

No. 10 Novak Djokovic def. Adrian Mannarino: 4-6, 6-2, 6-1

After dropping the opening set, Djokovic cruised through the second and third sets to earn a win over Adrian Mannarino.

Mannarino may have come out on the losing end, but he delivered the shot of the match. Down 2-5 in the second set, the 30-year-old Frenchman stayed alive by hitting a no-look forehand while chasing down a lob from Djokovic. He followed up with a forehand passing shot down the line:

Djokovic was a class above on the day despite being below his best. He committed three double faults and only succeeded on 53 percent of his first serves.

The turning point of the match may have been the fourth game of the second set. Mannarino was on serve down 1-2. Having broken Djokovic's serve in the previous game, Mannarino could have built a lot of momentum by levelling the set. Instead, he dropped serve and fell behind 1-3.

That was the opening Djokovic needed to go on and win the set and take the match.

Lesia Tsurenko def. No. 7 Garbine Muguruza: 2-6, 6-4, 6-4

Wednesday continued what has been a frustrating 2018 season for Muguruza, as she lost to unseeded Lesia Tsurenko in straight sets.

The Western & Southern Open is the third straight tournament in which the 24-year-old Spanish international exited in the second round.

Muguruza appeared to have the match in control in the third set after jumping out to a 4-1 lead. However, she unravelled and dropped the next five games. Her recent poor run of results may have been weighing heavily on her mind as she saw a win slip away.

Jose Morgado of Portuguese paper Record noted Muguruza will drop out of the top 10 as a result of her defeat. It's a relatively steep fall for a player who reached was the No. 1 player in the world last September.

The U.S. Open has historically been Muguruza's worst Grand Slam. She has advanced past the second round just once in five tries. Based on that, she may struggle to arrest her current slide.

No. 5 Grigor Dimitrov def. Mischa Zverev: 7-6(5), 7-5

Dimitrov survived a stern challenge from Zverev, winning in straight sets.

Zverev got out to a 3-1 lead in the opening but missed a golden opportunity to really put some pressure on the defending champion. Zverev was serving up 3-2. He and Dimitrov needed 15 points to decide the game, with Dimitrov earning a critical service break.

Rather than going up 4-2, Zverev was instead tied with Dimitrov. The two went back and forth until the tiebreaker, which Dimitrov won.

Neither player lost serve through the first 10 games of the second set, leading to a 5-5 tie. Dimitrov broke Zverev's serve in the 11th game, which turned the match in his favor for good.

Dimitrov now has a tough test against Djokovic ahead in the third round. Djokovic is 7-1 against Dimitrov, most recently at the Fever-Tree Championships in June.