Top-ranked Rafael Nadal downs John Isner in straight sets to gain China Open semis
Spain's Rafael Nadal is closing in on the yearend No. 1 ranking. AP

TOP-ranked Rafael Nadal moved into the semifinals of the China Open by beating sixth-seeded John Isner 6-4, 7-6 (0) on Friday.

The French Open and US Open champion has won five titles this season and is closing in on the year-end No. 1 ranking.

"I don't remember a lot of mistakes," Nadal said. "I went to the net very often. I did the things that I want to do, and I did it well, so very happy."

On the women's side, unseeded Carolina Garcia of France upset third-seeded Elina Svitolina of Ukraine, 6-7 (5), 7-5, 7-6 (6), in almost 3-1/2 hours to line up Petra Kvitova in the semifinals. Simona Halep, on course to becoming the No. 1 player in the world for the first time, faces French Open champion Jelena Ostapenko.

Nadal saved all three break points he faced against Isner. He will next play third-seeded Grigor Dimitrov, who defeated Roberto Bautista Agut, 7-6 (5), 4-6, 6-2.

Dimitrov spent time practicing with Nadal in Mallorca ahead of the hard-court season. The two also went fishing at sea.

"We catch a few ones (fish), but not very big," Nadal said. "But we had some good dinner."

Nick Kyrgios also advanced. The eighth-seeded Australian won when opponent Steve Darcis retired with a neck strain while trailing, 6-0, 3-0.

Kyrgios will take on second-seeded Alexander Zverev. The German beat Andrey Rublev, 6-2, 6-3, and qualified for the season-ending tournament in London.

"It's great for any player to qualify," said Zverev, who has five titles this season.

Second-ranked Halep moved into the women's semifinal by defeating Daria Kasatkina of Russia, 6-2, 6-1.

To bump Garbine Muguruza from No. 1, the Romanian needs to reach the final. Halep's quarterfinal win avenged her straight-sets loss to the 34th-ranked Kasatkina at Wuhan last week.

Kvitova defeated Czech countrywoman Barbora Strycova, 6-3, 6-4. Kvitova has won the last 24 matches she's played against fellow Czechs.

"We are pretty good friends from the Fed Cups," she said. "We know each other well. We practice a lot as well. Maybe it's extra motivation for us to play each other."

Ostapenko beat Sorana Cirstea, 6-4, 6-4, in an error-filled quarterfinal.

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