Djokovic downs Dimitrov in Beijing

The world number one continued his march to a fifth China Open title by defeating Grigor Dimitrov.

Novak Djokovic. Picture: Facebook.

BEIJING - World number one Novak Djokovic continued his march to a fifth China Open title by dismantling a flat Grigor Dimitrov in a one-sided quarter-final on Friday after women's top seed Serena Williams was forced to pull out through injury.

Briton Andy Murray will face Djokovic in the last four after also storming through with a 6-1 6-4 win over US Open champion Marin Cilic, while Maria Sharapova destroyed Svetlana Kuznetsova in an all-Russian women's quarter-final.

American world number one Williams, who had reached the last eight on the Beijing hard courts after a 6-1 1-6 6-2 win over Czech Lucie Safarova late on Thursday, cited a problem in her left knee for handing a walkover to Australian Sam Stosur.

It was the second tournament in a row the 33-year-old, who won her 18th grand slam singles title at the US Open last month, had been forced to withdraw after she quit her opening match at the Wuhan Open last week because of illness.

Bulgarian Dimitrov also looked off colour in his display against the Beijing expert Djokovic, who extended his record on the blue hard courts to 22-0 with a 6-2 6-4 win.

The Serb targeted the faltering backhand of the fifth seed in the opening set, which he took with breaks in the fourth and eighth games in an improved display after showing rust in his opening matches.

The second set seemed to be going the same way as Djokovic pushed Dimitrov back with some deep groundstrokes, while producing his trademark extensive court coverage to negate the threat of his opponent as he broke to lead 3-1.

Dimitrov finally showed some fight, breaking back with a thumping forehand cross court winner only to lose serve again in the next game to trail 4-2.

Djokovic looked set to serve out the match at 5-3 and 30-0 up but Dimitrov rallied again, breaking the Serb with the point of the match after a stunning backhand winner down the line at full stretch.

But rather than capitalise on the heroics, the world number 10 crumbled, giving up the match on a third double fault to leave his bid to qualify for the ATP Tour World Finals in London next month in trouble.

"It was pretty slow conditions because of the weather. It's a bit cold today, which I think suited more to my style of the game," Djokovic told reporters.

"I was trying to mix up the pace, give him high balls to the backhand, serve efficiently. Everything worked well. The second set was up and down. But generally it was a good performance."

Djokovic will face Murray, who, like Dimitrov, is chasing a place in the season-ending event for the top eight, in the last four.

Murray, eyeing back-to-back titles after Sunday's Shenzen Open triumph, put up a dominant display against Cilic, whose serve crumbled under pressure in the opening set.

The second set went neck-and-neck before Murray went 5-4 up and set up three match points, capitalising on the second when Cilic slipped while trying to return a backhand.

In the women's tournament, Stosur will take on Wimbledon champion Petra Kvitova in the semis after the Czech beat Italian Roberta Vinci 7-6 (7) 6-4.

World number three Kvitova, who won last week's event in Wuhan, mixed seven aces with six double faults as she battled through.

French Open champion Sharapova was far more dominant beating Kuznetsova 6-0 6-4 in an hour and 24 minutes to set up a semi-final clash with former world number one Ana Ivanovic.

Sharapova was broken only once and dropped just four games in the lop-sided contest to sail into only her second WTA semi-final since her victory at Roland Garros.