China Open

Maria Sharapova returns a shot during during the China Open final in Beijing on Sunday. (How Hwee Young / EPA)

Maria Sharapova returns a shot against Petra Kvitova. (Emmanuel Wong / Getty Images)

Petra Kvitova of the Czech Republic reacts during her woman’s singles final match against Maria Sharapova of Russia. (Petar Kujundzic / Reuters)

Petra Kvitova serves. (JASON LEE / Reuters Photo)

Novak Djokovic returns a shot to Tomas Berdych during the China Open men’s singles final. (Feng Li / Getty Images)

Novak Djokovic volleys with Tomas Berdych. (How Hwee Young / EPA)

Novak Djokovic of Serbia returns a shot against Tomas Berdych of the Czech Republic. (Emmanuel Wong / Getty Images)

Tomas Berdych returns a shot during the China Open at the National Tennis Center in Beijing. (Feng Li / Getty Images)

Novak Djokovic falls during his match. (HOW HWEE YOUNG / EPA)

Novak Djokovic misses a ball. (Emmanuel Wong / Getty Images)

Novak Djokovic celebrates winning the men’s China Open championship. (Feng Li / Getty Images)

Maria Sharapova reacts after winning a point. (Goh Chai Hin / AFP/Getty Images)

Maria Sharapova poses with her trophy during the medal ceremony. (Emmanuel Wong / Getty Images)

Rafael Nadal of Spain hits a return to Martin Klizan. (Jason Lee / Reuters)

Rafael Nadal of Spain plays a forehand. (Chris Hyde / Getty Images)

Rafael Nadal rests during his match against Martin Klizan. (Chris Hyde / Getty Images)

Martin Klizan of Slovakia returns a shot against Spain’s Rafael Nadal. (Goh Chai Hin / AFP/Getty Images)

Martin Klizan celebrates his quarterfinal victory over Rafael Nadal at Beijing’s National Tennis Center. (Rolex Dela Pena / EPA)

Rafael Nadal waves to the crowd after losing to Martin Klizan during their China Open quarterfinal match in Beijing on Friday. (Rolex Dela Pena / EPA)

Rafael Nadal walks off the playing court after the loss. (Rolex Dela Pena / EPA)

Rafael Nadal of Spain speaks to media after losing to Martin Klizan. (Chris Hyde / Getty Images)

Maria Sharapova returns a shot to Svetlana Kuznetsova during their all-Russian quarterfinal match on Friday. (Goh Chai Hin / AFP/Getty Images)

Svetlana Kuznetsova returns a shot against Maria Sharapova. (Goh Chai Hin / AFP/Getty Images)

Maria Sharapova returns a shot to Svetlana Kuznetsova. (Feng Li / Getty Images)

Svetlana Kuznetsova reacts during her match against Maria Sharapova. (Feng Li / Getty Images)

Maria Sharapova of Russia celebrates her victory. (Feng Li / Getty Images)

Serena Williams talks to reporters about her knee injury. Williams withdrew from the China Open on Friday. (Fred Dufour / AFP/Getty Images)

Novak Djokovic returns a shot against Grigor Dimitrov during a quarterfinal match at the China Open in Beijing. (Goh Chai Hin / AFP/Getty Images)

Novak Djokovic reaches for a shot back to Grigor Dimitrov. (Goh Chai Hin / AFP/Getty Images)

Grigor Dimitrov volleys with Novak Djokovic. (Goh Chai Hin / AFP/Getty Images)

Petra Kvitova returns a shot against Roberta Vinci. (Emmanuel Wong / Getty Images)

American John Isner returns a shot against Tomas Berdych of the Czech Republic. (Feng Li / Getty Images)

A costumed mascot waits for the men’s quarterfinal match between Rafael Nadal and Martin Klizan. (Jason Lee / Reuters)

Rafael Nadal adjusts his headband during his match against Peter Gojowczyk at the China Open tennis tournament in Beijing on Thursday. (Petar Kujundzic / Reuters)

Rafael Nadal serves against Peter Gojowczyk during their second-round match. (Wang Zhao / AFP/Getty Images)

Rafael Nadal reacts after winning a point. (Petar Kujundzic / Reuters)

Two fans cheer after Rafael Nadal of Spain won his match against Peter Gojowczyk of Germany. (Wang Zhao / AFP/Getty Images)

Serena Williams lunges for a shot during her third-round match with Lucie Safarova. (Wang Zhao / AFP/Getty Images)

Serena Williams reacts after winning a point against Lucie Safarova. (Petar Kujundzic / Reuters)

Serena Williams rests during a break. (Wang Zhao / AFP/Getty Images)

A China Open ball girl waits during a men’s singles second-round match at the National Tennis Center in Beijing. (Fred Dufour / AFP/Getty Images)

Ana Ivanovic backhands a shot in her match against Sabine Lisicki. (Chris Hyde / Getty Images)

Andy Murray stretches to return Pablo Cuevas’ shot. (Feng Li / Getty Images)

Andy Murray reacts to missing a shot. (Petar Kujundzic / Reuters)

Andy Murray reacts after losing a point to Pablo Cuevas. (Wang Zhao / AFP/Getty Images)

Simona Halep celebrates beating Andrea Petkovic. But Halep aggravated a hip injury and withdrew from the tournament. (Feng Li / Getty Images)

Simona Halep receive medical treatment. (Wang Zhao / AFP/Getty Images)

Marin Cilic returns a shot against Joao Sousa. (FRED DUFOUR / AFP/Getty Images)

Grigor Dimitrov volleys with Pablo Andujar. (FRED DUFOUR / AFP/Getty Images)

Grigor Dimitrov returns a shot against Pablo Andujar. (Emmanuel Wong / Getty Images)

Grigor Dimitrov returns a shot to Pablo Andujar during day six of the China Open. (Emmanuel Wong / Getty Images)

Samantha Stosur signs autographs after winning against Alize Cornet. (Fred Dufour / AFP/Getty Images)

Maria Sharapova returns a shot against Elina Svitolina during the second round of the China Open tennis tournament in Beijing on Tuesday. (Fred Dufour / AFP/Getty Images)

Serena Williams prepares to play against Tsvetana Pironkova. (Fred Dufour / AFP/Getty Images)

Serena Williams reacts during her second round match. (Diego Azubel / EPA)

Serena Williams returns to Tsevatana Pironkova. (Diego Azubel / EPA)

Elina Svitolina volleys to Maria Sharapova. (Diego Azubel / EPA)

Tsvetana Pironkova serves to Serena Williams. (Petar Kujundzic / Reuters )

Rafael Nadal serves against Richard Gasquet during their first round match. (Diego Azubel / EPA)

Caroline Garcia returns a shot to Venus Williams. (Wang Zhao / AFP/Getty Images)

Andy Murray lunges for a return. (Wang Zhao / AFP/Getty Images)

Andy Murray reacts during his first-round match against Jerzy Janowicz. (Diego Azubel / EPA)

Chinese tennis player Li Na reacts during her retirement ceremony on the sidelines of the China Open. (Diego Azubel / EPA)

Li Na tears up during her farewell ceremony. (Goh Chai Hin / AFP/Getty Images)

Li Na tears up as she bids farewell to her fans. (Goh Chai Hin / AFP/Getty Images)

Li Na looks to the crowd during her retirement ceremony. (Goh Chai Hin / AFP/Getty Images)

Petra Kvitova hugs Li Na. (Petar Kujundzic / Reuters)

Simona Halep reacts after losing a point to Lin Zhu. (Wang Zhao / AFP/Getty Images)

Simona Halep celebrates her victory over Lin Zhu, (Wang Zhao / AFP/Getty Images)

Fans react to Rafael Nadal taking off his shirt after Nadal defeated Richard Gasquet. (Fred Dufour / AFP/Getty Images)

Rafael Nadal returns a shot against Richard Gasquet. (Goh Chai Hin / AFP/Getty Images)

Venus Williams returns to Caroline Garcia during the China Open tennis tournament at the National Tennis Center in Beijing on Tuesday. (Wang Zhao / AFP/Getty Images)